Support target-scoped trauma mechanics

docs/DESIGN_SYSTEM.md

@@ -2005,20 +2005,33 @@ branches, ordered outcomes, and the generated read-only script. Use connected
 panels and restrained borders to preserve the hierarchy; do not present the
 typed graph as an undifferentiated form.
 
+Talent editors place that surface inside the shared `modeling-disclosure`
+pattern. New `CAPTURED ONLY` Talents start with an empty program and a collapsed
+`COMBAT MODELING` summary so authors can record identity, image, and source
+description first. Existing modeled Talents open the disclosure when edited.
+Mechanic validation errors open it and keep the relevant error text visible.
+The summary reports `CAPTURE ONLY · MODEL LATER` or the configured branch count
+in text. Its native disclosure semantics preserve keyboard and assistive
+technology support; mobile targets remain at least 44 pixels tall.
+
 The direct-event picker reads the 19 normalized events from the code-defined
 event registry. Use searchable single-assignment because the vocabulary exceeds
 the compact segmented-choice limit. Each branch presents its event, match
 policy and parameters, optional cooldown, state mutations, and outcomes.
 Recipe-generated predicates and weights remain visible in the generated
 script. State rows expose label, agent or target scope, initial value, bounds,
-best-case value, and optional expiry. Outcome rows expose kind, target scope,
-Attribute or resource when applicable, value basis, state scaling, phase, and
-every source-specific value column. The Value Model control supports static
-values, live Attribute percentages, event fields, reducer output, source-defined
-scenario controls, and OS Protocol upgrade scaling where the source permits it.
-Selecting a live Attribute uses the shared searchable single-assignment pattern
-and displays the Attribute's unit. Label the percentage-normalized model
-`ATTRIBUTE ÷ 100` so authors can see the transform applied to the stored value.
+best-case value, and optional expiry. A state change that writes a target pool
+uses a `STATE OWNER` segmented control with `EVENT TARGET` and `EVENT ACTOR`;
+the selected owner remains visible in the generated script. Outcome rows expose
+kind, target scope, Attribute or resource when applicable, value basis, state
+scaling, phase, and every source-specific value column. The Value Model control
+supports static values, live Attribute totals, percentage-normalized Attribute
+values, event fields, reducer output, source-defined scenario controls, and OS
+Protocol upgrade scaling where the source permits it. Selecting either
+Attribute model uses the shared searchable single-assignment pattern and
+displays the Attribute's unit. Label the direct model `LIVE ATTRIBUTE`. Label
+the percentage-normalized model `ATTRIBUTE ÷ 100` so authors can see the
+transform applied to the stored value.
 Restoration outcomes also expose an
 `INSTANT` or `CONTINUOUS` segmented choice. Continuous delivery reveals one
 required duration field and describes the configured value as the total

docs/architecture.md

@@ -398,7 +398,10 @@ normalized events are `shot_fired`, `weapon_hit`, `skill_deployed`,
 `movement_snapshot`, `proximity_snapshot`, `firing_started`, `firing_stopped`,
 `reload_started`, `reload_completed`, `weapon_swapped`, and `tick`. Event
 details such as target, distance, critical state, source, movement, and nearby
-counts travel as typed event values.
+counts travel as typed event values. The event registry publishes authoritative
+field metadata where branches need a bounded contract. For example,
+`weapon_hit.values.headshot` is a boolean that distinguishes headshots from
+body shots.
 
 The optional Action Family catalog provides authoring recipes for common
 mechanics. Applying a recipe copies its typed scenario inputs, state pools, and
@@ -408,6 +411,12 @@ dependency. Adding another recipe appends branches. Replacing a program with a
 recipe requires confirmation because replacement discards the current branch
 graph.
 
+A Talent may save an empty `captured_only` program while an author records its
+name, category, image, and source description. The registry marks that Talent
+`CONFIG REQUIRED`, and calculations exclude it. Changing readiness to `ready`
+or `requires_assumptions` restores strict branch, numbered-outcome, and
+description-placeholder validation.
+
 The program graph uses three child tables:
 
 - `conditional_effect_state_pools` defines agent- or target-scoped flags,
@@ -418,14 +427,16 @@ The program graph uses three child tables:
   state mutations, and optional recipe provenance. Reducers convert event
   streams into counts, distinct or consecutive matches, sliding windows,
   durations, intervals, or derived values. Mutations can set, add, consume,
-  clear, derive, or transfer state.
+  clear, derive, or transfer state. A mutation may bind a target-scoped pool to
+  the current event target, event actor, or another typed entity selector. Each
+  target owns an independent value and expiry timer.
 - `conditional_effect_outcomes` applies Attribute modifiers, direct damage,
   restoration, resource costs, or markers. Each outcome names its target scope,
   value basis, optional resource or Attribute, combat timing, optional state
   band, and phase: `on_event`, `after_event`, `on_enter`, `on_exit`, or
   `while_active`. One typed value or expression exists for every variant
   required by the owning source. The common value models are static values,
-  live Attribute percentages, event-field values, reducer output,
+  live Attribute values, percentage-normalized Attribute values, event-field values, reducer output,
   source-defined scenario values, and OS Protocol upgrade scaling. Restoration
   outcomes may deliver their total immediately or continuously over an explicit
   duration.
@@ -436,6 +447,13 @@ convert event streams into activations or derived values. The runtime applies
 state mutations, enforces pool bounds and expiry, emits outcomes in phase order,
 and records telemetry for each activation.
 
+Each write to an expiring pool refreshes its timer. When a pool expires,
+`on_exit` outcomes evaluate stack thresholds and per-stack expressions against
+the final value before reset. The runtime records the bound target on emitted
+outcomes. A one-second target debuff with a one-second damage cadence can
+therefore resolve once at its refreshed shared expiry without inventing
+intermediate ticks.
+
 Live Attribute references use a stable Attribute ID and read the authoritative
 loadout total that the builder captures for the evaluation pass. Percentage
 Attributes retain their displayed units, so an expression that applies a

src/app.css

@@ -2393,3 +2393,19 @@
 .field-error{display:block;margin:5px 0 0;color:var(--shd-danger);font-size:var(--shd-type-telemetry);line-height:1.4}
 .mechanic-field-error{padding-left:10px;border-left:2px solid var(--shd-danger)}
 @media(max-width:560px){.validation-summary a{grid-template-columns:1fr;gap:1px}}
+
+/* Collapsible modeled-data workspace for capture-first ISAC editors. */
+.modeling-disclosure{margin-top:10px;border:1px solid var(--shd-border);background:var(--shd-surface)}
+.modeling-disclosure>summary{min-height:52px;display:flex;align-items:center;justify-content:space-between;gap:12px;padding:9px 11px;list-style:none;background:var(--shd-surface-raised);cursor:pointer}
+.modeling-disclosure>summary::-webkit-details-marker{display:none}
+.modeling-disclosure>summary span{display:grid;gap:3px}
+.modeling-disclosure>summary b,.modeling-disclosure>summary strong{font-size:var(--shd-type-telemetry);font-weight:900;letter-spacing:.9px}
+.modeling-disclosure>summary small{color:var(--shd-text-muted);font-size:var(--shd-type-telemetry);letter-spacing:.5px}
+.modeling-disclosure>summary strong{color:var(--shd-orange)}
+.modeling-disclosure>summary:hover,.modeling-disclosure>summary:focus-visible{background:var(--shd-surface-active);box-shadow:inset 2px 0 var(--shd-orange);outline:none}
+.modeling-disclosure[open]>summary{border-bottom:1px solid var(--shd-border);box-shadow:inset 2px 0 var(--shd-orange)}
+.modeling-disclosure.validation-area-error{border-color:var(--shd-danger)}
+.modeling-disclosure.validation-area-error>summary{box-shadow:inset 2px 0 var(--shd-danger)}
+.modeling-content{padding:10px}
+@media(max-width:560px){.modeling-disclosure>summary{min-height:56px}.modeling-content{padding:7px}}
+@media(prefers-reduced-motion:reduce){.modeling-disclosure>summary{transition:none}}

src/lib/calculations/conditional.test.ts

@@ -43,7 +43,7 @@ const shot = (
 
 describe('trigger action registry', () => {
 	it('owns every action and validates discriminated parameters', () => {
-		expect(Object.keys(TRIGGER_ACTION_REGISTRY)).toHaveLength(15);
+		expect(Object.keys(TRIGGER_ACTION_REGISTRY)).toHaveLength(16);
 		expect(validateTriggerConfiguration('same_target_hits_within_window', {
 			hitsRequired: 9,
 			windowSeconds: 3
@@ -197,6 +197,18 @@ describe('evaluateConditionalProgram', () => {
 		});
 	});
 
+	it('treats an explicit non-headshot hit as a body shot', () => {
+		const result = evaluateConditionalProgram(program({
+			action: 'body_shot',
+			params: {}
+		}), [
+			shot(1, 'alpha', true, false),
+			shot(2, 'alpha', true, true),
+			shot(3, 'alpha', false, false)
+		], { mode: 'encounter', encounterSeconds: 5 });
+		expect(result.activations.map((activation) => activation.at)).toEqual([1]);
+	});
+
 	it('refreshes one shared duration and clears every stack on expiry', () => {
 		const result = evaluateConditionalProgram(program({
 			action: 'damage_taken',

src/lib/calculations/conditional.ts

@@ -6,6 +6,7 @@ export const TRIGGER_ACTION_KEYS = [
 	'while_firing',
 	'health_threshold_bands',
 	'headshot',
+	'body_shot',
 	'headshot_kill',
 	'weapon_kill',
 	'target_hit_within_distance',
@@ -52,6 +53,7 @@ export type TriggerParamsByAction = {
 	while_firing: EmptyTriggerParams;
 	health_threshold_bands: HealthThresholdParams;
 	headshot: EmptyTriggerParams;
+	body_shot: EmptyTriggerParams;
 	headshot_kill: EmptyTriggerParams;
 	weapon_kill: EmptyTriggerParams;
 	target_hit_within_distance: DistanceParams;
@@ -374,6 +376,12 @@ export const TRIGGER_ACTION_REGISTRY: Readonly<Record<TriggerActionKey, TriggerA
 		validate: validateEmpty,
 		summarize: () => 'Land a headshot.'
 	},
+	body_shot: {
+		key: 'body_shot',
+		label: 'Body shot',
+		validate: validateEmpty,
+		summarize: () => 'Land a non-headshot weapon hit.'
+	},
 	headshot_kill: {
 		key: 'headshot_kill',
 		label: 'Headshot kill',
@@ -611,6 +619,10 @@ function eventCandidates(
 			return events
 				.filter((event): event is ShotEvent => event.kind === 'shot' && event.hit && event.headshot === true)
 				.map((event) => ({ at: event.at, outcomeKey: null }));
+		case 'body_shot':
+			return events
+				.filter((event): event is ShotEvent => event.kind === 'shot' && event.hit && event.headshot === false)
+				.map((event) => ({ at: event.at, outcomeKey: null }));
 		case 'headshot_kill':
 			return events
 				.filter((event): event is EnemyKilledEvent => event.kind === 'enemy_killed' && event.headshot === true)

src/lib/calculations/mechanic-editor.test.ts

@@ -54,6 +54,41 @@ const draft = (): ConditionalMechanicDraftV1 => ({
 });
 
 describe('conditional mechanic authoring payload', () => {
+	it('accepts an empty captured-only program for deferred modeling', () => {
+		const partial: ConditionalMechanicDraftV1 = {
+			version: 1,
+			simulationReadiness: 'captured_only',
+			scenarioInputs: [],
+			pools: [],
+			clauses: []
+		};
+		const result = parseConditionalMechanicDraft(partial, {
+			variantKeys: ['I', 'II']
+		});
+		expect(result.ok).toBe(true);
+		if (!result.ok) return;
+		expect(result.value.draft).toEqual(partial);
+		expect(result.value.programs.I.clauses).toEqual([]);
+		expect(result.value.programs.II.clauses).toEqual([]);
+	});
+
+	it('requires a branch after a partial program is marked calculation-ready', () => {
+		const partial: ConditionalMechanicDraftV1 = {
+			version: 1,
+			simulationReadiness: 'ready',
+			scenarioInputs: [],
+			pools: [],
+			clauses: []
+		};
+		const result = parseConditionalMechanicDraft(partial, {
+			variantKeys: ['I', 'II']
+		});
+		expect(result.ok).toBe(false);
+		if (!result.ok) {
+			expect(result.errors).toContain('A simulation-ready mechanic requires at least one clause.');
+		}
+	});
+
 	it('builds one validated runtime program per exact source variant', () => {
 		const result = parseConditionalMechanicDraft(draft(), {
 			variantKeys: ['I', 'II'],
@@ -263,6 +298,98 @@ describe('conditional mechanic authoring payload', () => {
 		}
 	});
 
+	it('preserves target entity mutations and state-scaled exit outcomes', () => {
+		const targeted: ConditionalMechanicDraftV1 = {
+			version: 1,
+			simulationReadiness: 'ready',
+			scenarioInputs: [],
+			pools: [{
+				key: 'marked-target',
+				label: 'Marked Target',
+				stateKind: 'target_mark',
+				scope: 'target',
+				initial: 0,
+				min: 0,
+				max: 1
+			}],
+			clauses: [{
+				key: 'detonate-mark',
+				event: 'enemy_killed',
+				reducer: { kind: 'none' },
+				mutations: [{
+					kind: 'set',
+					pool: 'marked-target',
+					entity: { kind: 'event_target' },
+					value: 1
+				}],
+				outcomes: [{
+					key: 'target-damage',
+					label: 'Target Damage',
+					phase: 'on_exit',
+					kind: 'direct_damage',
+					scope: 'target',
+					basis: 'flat',
+					statePool: 'marked-target',
+					perStack: true,
+					variants: {
+						base: {
+							value: 240,
+							expression: {
+								op: 'multiply',
+								left: 240,
+								right: {
+									op: 'divide',
+									left: {
+										ref: {
+											source: 'attribute',
+											attributeId: 'firepower-multiplier'
+										}
+									},
+									right: 100
+								}
+							}
+						}
+					}
+				}]
+			}]
+		};
+		const result = parseConditionalMechanicDraft(targeted, {
+			variantKeys: ['base'],
+			allowedAttributeIds: new Set(['firepower-multiplier'])
+		});
+
+		expect(result.ok).toBe(true);
+		if (!result.ok) return;
+		expect(result.value.draft).toMatchObject(targeted);
+		expect(result.value.programs.base).toMatchObject({
+			pools: [{ key: 'marked-target', scope: 'target' }],
+			clauses: [{
+				mutations: [{
+					kind: 'set',
+					pool: 'marked-target',
+					entity: { kind: 'event_target' },
+					value: 1
+				}],
+				outcomes: [{
+					phase: 'on_exit',
+					kind: 'direct_damage',
+					statePool: 'marked-target',
+					perStack: true,
+					value: {
+						right: {
+							left: {
+								ref: {
+									source: 'attribute',
+									attributeId: 'firepower-multiplier'
+								}
+							}
+						}
+					}
+				}]
+			}]
+		});
+	});
+
 	it('rejects outcome fields that are absent from the canonical capability manifest', () => {
 		const unsupported = draft();
 		(unsupported.clauses[0].outcomes[0] as unknown as Record<string, unknown>).cadence =

src/lib/calculations/mechanic-persistence.test.ts

@@ -215,6 +215,113 @@ describe('conditional-effect persistence adapter', () => {
 		expect(result.errors).toContain('Outcome 1 continuous delivery requires a positive duration.');
 	});
 
+	it('preserves target pool mutations, exit outcomes, and live Attribute references', () => {
+		const firepowerMultiplierId = '82a95611-283b-4fd8-a6ed-3567a316f36e';
+		const result = adaptConditionalEffectProgram({
+			rule: rule(),
+			statePools: [pool({
+				state_key: 'marked-target',
+				label: 'Marked Target',
+				state_kind: 'target_mark',
+				state_scope: 'target',
+				maximum_value: 1,
+				best_case_value: 1
+			})],
+			clauses: [clause({
+				trigger_id: null,
+				event_kind: 'enemy_killed',
+				parameters_json: '{}',
+				mutations_json: JSON.stringify([{
+					kind: 'set',
+					pool: 'marked-target',
+					entity: { kind: 'event_target' },
+					value: 1
+				}])
+			})],
+			outcomes: [outcome({
+				effect_key: 'marked-target-detonation',
+				application_kind: 'direct_damage',
+				effect_scope: 'target',
+				stat_attribute_id: null,
+				value: 240,
+				value_expression_json: JSON.stringify({
+					op: 'multiply',
+					left: 240,
+					right: {
+						op: 'divide',
+						left: {
+							ref: {
+								source: 'attribute',
+								attributeId: firepowerMultiplierId
+							}
+						},
+						right: 100
+					}
+				}),
+				value_scaling: 'per_state_unit',
+				damage_basis: 'flat',
+				application_phase: 'on_exit',
+				min_state_value: null
+			})],
+			triggers: []
+		}, { name: 'Target Detonation', variantKey: 'I' });
+
+		expect(result.errors).toEqual([]);
+		expect(result.program?.pools?.[0]).toMatchObject({
+			key: 'marked-target',
+			scope: 'target'
+		});
+		expect(result.program?.clauses[0]).toMatchObject({
+			mutations: [{
+				kind: 'set',
+				pool: 'marked-target',
+				entity: { kind: 'event_target' },
+				value: 1
+			}],
+			outcomes: [{
+				phase: 'on_exit',
+				kind: 'direct_damage',
+				scope: 'target',
+				statePool: 'marked-target',
+				perStack: true,
+				value: {
+					op: 'multiply',
+					left: 240,
+					right: {
+						op: 'divide',
+						left: {
+							ref: {
+								source: 'attribute',
+								attributeId: firepowerMultiplierId
+							}
+						},
+						right: 100
+					}
+				}
+			}]
+		});
+	});
+
+	it('rejects malformed mutation entity selectors from persisted JSON', () => {
+		const result = adaptConditionalEffectProgram({
+			rule: rule(),
+			statePools: [pool({ state_scope: 'target' })],
+			clauses: [clause({
+				mutations_json: JSON.stringify([{
+					kind: 'set',
+					pool: 'effect',
+					entity: { kind: 'event_field', path: '' },
+					value: 1
+				}])
+			})],
+			outcomes: [outcome()],
+			triggers: [{ id: 'trigger-1', action_key: 'same_target_hits_within_window' }]
+		}, { variantKey: 'I' });
+
+		expect(result.status).toBe('INVALID');
+		expect(result.errors).toContain('Clause 1 mutations must be an array of valid state mutations.');
+	});
+
 	it('adapts the Happy Survival branches, explicit cadence, health timing, and upgrade references', () => {
 		const upgradeScale = {
 			op: 'add',

src/lib/calculations/mechanic-persistence.ts

@@ -174,20 +174,43 @@ function requiredNumber(value: DatabaseValue, path: string, errors: string[]) {
 	return result ?? 0;
 }
 
+function isEntitySelector(value: unknown) {
+	if (!object(value) || typeof value.kind !== 'string') return false;
+	if (value.kind === 'agent' || value.kind === 'event_actor' || value.kind === 'event_target') {
+		return true;
+	}
+	return value.kind === 'event_field'
+		&& typeof value.path === 'string'
+		&& Boolean(value.path.trim());
+}
+
+function isValueReference(value: unknown) {
+	if (!object(value) || typeof value.source !== 'string') return false;
+	if (value.source === 'event' || value.source === 'equipment') {
+		return typeof value.path === 'string' && Boolean(value.path.trim());
+	}
+	if (value.source === 'combat') {
+		return typeof value.path === 'string'
+			&& Boolean(value.path.trim())
+			&& (value.timing === undefined || value.timing === 'pre_event' || value.timing === 'current');
+	}
+	if (value.source === 'attribute') {
+		return typeof value.attributeId === 'string' && Boolean(value.attributeId.trim());
+	}
+	if (value.source === 'scenario') {
+		return typeof value.key === 'string' && Boolean(value.key.trim());
+	}
+	if (value.source === 'reducer') return true;
+	return value.source === 'pool'
+		&& typeof value.pool === 'string'
+		&& Boolean(value.pool.trim())
+		&& (value.entity === undefined || isEntitySelector(value.entity));
+}
+
 function isNumericExpression(value: unknown): value is NumericExpression {
 	if (finite(value)) return true;
 	if (!object(value)) return false;
-	if ('ref' in value) {
-		if (!object(value.ref) || typeof value.ref.source !== 'string') return false;
-		const source = value.ref.source;
-		if (source === 'event' || source === 'combat' || source === 'equipment') {
-			return typeof value.ref.path === 'string';
-		}
-		if (source === 'scenario') return typeof value.ref.key === 'string';
-		if (source === 'reducer') return true;
-		if (source === 'pool') return typeof value.ref.pool === 'string';
-		return false;
-	}
+	if ('ref' in value) return isValueReference(value.ref);
 	if (value.op === 'clamp') {
 		return isNumericExpression(value.value)
 			&& isNumericExpression(value.min)
@@ -233,14 +256,20 @@ function isReducer(value: unknown): value is Reducer {
 function isMutation(value: unknown): value is ClauseMutation {
 	if (!object(value) || typeof value.kind !== 'string') return false;
 	if (value.kind === 'none') return true;
-	if (value.kind === 'clear') return typeof value.pool === 'string';
+	if (value.kind === 'clear') {
+		return typeof value.pool === 'string'
+			&& (value.entity === undefined || isEntitySelector(value.entity));
+	}
 	if (value.kind === 'transfer') {
-		return typeof value.pool === 'string' && object(value.from) && object(value.to)
+		return typeof value.pool === 'string'
+			&& isEntitySelector(value.from)
+			&& isEntitySelector(value.to)
 			&& (value.value === undefined || value.value === 'all' || isNumericExpression(value.value));
 	}
 	return ['add', 'set', 'consume', 'derive'].includes(value.kind)
 		&& typeof value.pool === 'string'
-		&& isNumericExpression(value.value);
+		&& isNumericExpression(value.value)
+		&& (value.entity === undefined || isEntitySelector(value.entity));
 }
 
 function parseScenarioInputs(

src/lib/calculations/mechanic-recipes.test.ts

@@ -25,6 +25,7 @@ const paramsByAction: Record<TriggerActionKey, unknown> = {
 		]
 	},
 	headshot: {},
+	body_shot: {},
 	headshot_kill: {},
 	weapon_kill: {},
 	target_hit_within_distance: { meters: 15 },
@@ -96,6 +97,27 @@ describe('mechanic recipe registry', () => {
 		});
 	});
 
+	it('maps head and body shots to authoritative weapon-hit predicates', () => {
+		for (const [action, headshot] of [['headshot', true], ['body_shot', false]] as const) {
+			expect(seedFor(action).clauses[0]).toMatchObject({
+				when: 'weapon_hit',
+				if: {
+					kind: 'all',
+					predicates: [
+						{ kind: 'exists', value: { source: 'event', path: 'targetId' } },
+						{ kind: 'exists', value: { source: 'event', path: 'values.headshot' } },
+						{
+							kind: 'compare',
+							left: { source: 'event', path: 'values.headshot' },
+							operator: 'eq',
+							right: headshot
+						}
+					]
+				}
+			});
+		}
+	});
+
 	it('models firing triggers as explicit lifecycle branches', () => {
 		const continuous = seedFor('continuous_firing_duration');
 		expect(continuous.pools).toEqual([expect.objectContaining({ key: 'firing-active', max: 1 })]);

src/lib/calculations/mechanic-recipes.ts

@@ -251,7 +251,23 @@ export const MECHANIC_RECIPE_REGISTRY: Readonly<MechanicRecipeRegistry> = {
 	headshot: {
 		key: 'headshot',
 		createSeed: (_params) => supported({ clauses: [directClause('headshot', 'weapon_hit', {
-			kind: 'compare', left: eventValue('headshot'), operator: 'eq', right: true
+			kind: 'all',
+			predicates: [
+				targetExists,
+				{ kind: 'exists', value: eventValue('headshot') },
+				{ kind: 'compare', left: eventValue('headshot'), operator: 'eq', right: true }
+			]
+		})] })
+	},
+	body_shot: {
+		key: 'body_shot',
+		createSeed: (_params) => supported({ clauses: [directClause('body-shot', 'weapon_hit', {
+			kind: 'all',
+			predicates: [
+				targetExists,
+				{ kind: 'exists', value: eventValue('headshot') },
+				{ kind: 'compare', left: eventValue('headshot'), operator: 'eq', right: false }
+			]
 		})] })
 	},
 	headshot_kill: {

src/lib/calculations/mechanic.test.ts

@@ -1,5 +1,6 @@
 import { describe, expect, it } from 'vitest';
 import {
+	MECHANIC_EVENT_REGISTRY,
 	evaluateMechanicProgram,
 	formatMechanicProgram,
 	validateMechanicProgram,
@@ -14,6 +15,16 @@ const custom = (encounterSeconds = 30, inputs: Record<string, number | boolean>
 });
 
 describe('structured mechanic runtime', () => {
+	it('advertises the authoritative weapon-hit target and headshot fields', () => {
+		expect(MECHANIC_EVENT_REGISTRY.weapon_hit).toMatchObject({
+			description: expect.stringContaining('headshot boolean'),
+			fields: [
+				{ path: 'targetId', label: 'Target ID', type: 'string' },
+				{ path: 'values.headshot', label: 'Headshot', type: 'boolean' }
+			]
+		});
+	});
+
 	it('models Superior Firepower as same-target sliding hits and one shared expiring stack pool', () => {
 		const superiorFirepower: MechanicProgram = {
 			id: 'superior-firepower',
@@ -512,6 +523,151 @@ describe('structured mechanic runtime', () => {
 		]);
 	});
 
+	it('caps and refreshes target-scoped stacks independently', () => {
+		const program: MechanicProgram = {
+			id: 'target-trauma',
+			name: 'Target Trauma',
+			pools: [{
+				key: 'trauma',
+				label: 'Trauma',
+				scope: 'target',
+				initial: 0,
+				min: 0,
+				max: 10,
+				expiresAfterSeconds: 1
+			}],
+			clauses: [
+				{
+					id: 'body-stack',
+					when: 'weapon_hit',
+					if: {
+						kind: 'compare',
+						left: { source: 'event', path: 'values.headshot' },
+						operator: 'eq',
+						right: false
+					},
+					reducer: { kind: 'none' },
+					mutations: [{
+						kind: 'add',
+						pool: 'trauma',
+						entity: { kind: 'event_target' },
+						value: 1
+					}]
+				},
+				{
+					id: 'head-stack',
+					when: 'weapon_hit',
+					if: {
+						kind: 'compare',
+						left: { source: 'event', path: 'values.headshot' },
+						operator: 'eq',
+						right: true
+					},
+					reducer: { kind: 'none' },
+					mutations: [{
+						kind: 'add',
+						pool: 'trauma',
+						entity: { kind: 'event_target' },
+						value: 2
+					}]
+				}
+			]
+		};
+		const result = evaluateMechanicProgram(program, [
+			{ kind: 'weapon_hit', at: 0, targetId: 'enemy-a', values: { headshot: false } },
+			{ kind: 'weapon_hit', at: 0.25, targetId: 'enemy-b', values: { headshot: false } },
+			{ kind: 'weapon_hit', at: 0.5, targetId: 'enemy-a', values: { headshot: true } },
+			...Array.from({ length: 5 }, (_, index): MechanicEvent => ({
+				kind: 'weapon_hit',
+				at: 0.55 + index * 0.05,
+				targetId: 'enemy-a',
+				values: { headshot: true }
+			}))
+		], custom(0.9));
+		expect(result.status).toBe('OK');
+		expect(result.finalState).toEqual([
+			expect.objectContaining({
+				pool: 'trauma',
+				entityId: 'enemy-a',
+				value: 10,
+				expiresAt: 1.75
+			}),
+			expect.objectContaining({
+				pool: 'trauma',
+				entityId: 'enemy-b',
+				value: 1,
+				expiresAt: 1.25
+			})
+		]);
+	});
+
+	it('uses the prior target stack count for live-Attribute damage on pool exit', () => {
+		const skillDamageId = 'skill-damage';
+		const program: MechanicProgram = {
+			id: 'precise-trauma',
+			name: 'Precise Trauma',
+			pools: [{
+				key: 'trauma',
+				label: 'Trauma',
+				scope: 'target',
+				initial: 0,
+				min: 0,
+				max: 10,
+				expiresAfterSeconds: 1
+			}],
+			clauses: [{
+				id: 'apply-trauma',
+				when: 'weapon_hit',
+				reducer: { kind: 'none' },
+				mutations: [{
+					kind: 'add',
+					pool: 'trauma',
+					entity: { kind: 'event_target' },
+					value: 2
+				}],
+				outcomes: [{
+					id: 'trauma-damage',
+					label: 'Trauma Damage',
+					phase: 'on_exit',
+					kind: 'direct_damage',
+					scope: 'target',
+					basis: 'flat',
+					value: { ref: { source: 'attribute', attributeId: skillDamageId } },
+					statePool: 'trauma',
+					perStack: true,
+					minStacks: 2
+				}]
+			}]
+		};
+		const result = evaluateMechanicProgram(
+			program,
+			[{ kind: 'weapon_hit', at: 0, targetId: 'enemy-a', values: { headshot: true } }],
+			custom(2),
+			{
+				maxHealth: 100,
+				currentHealth: 100,
+				attributes: { [skillDamageId]: 75 }
+			}
+		);
+		expect(result.status).toBe('OK');
+		expect(result.outcomes).toMatchObject([{
+			outcomeId: 'trauma-damage',
+			targetId: 'enemy-a',
+			at: 1,
+			phase: 'on_exit',
+			value: 150,
+			resolvedValue: 150,
+			appliedValue: 150,
+			stateValue: 2
+		}]);
+		expect(result.finalState).toContainEqual(expect.objectContaining({
+			pool: 'trauma',
+			entityId: 'enemy-a',
+			value: 0,
+			expiresAt: null
+		}));
+	});
+
 	it('models scaled OS Protocol restoration, an unscaled Health cost, and post-cost bonus damage', () => {
 		const upgradeScale = {
 			op: 'add' as const,

src/lib/calculations/mechanic.ts

@@ -25,6 +25,11 @@ export type MechanicEventDefinition = {
 	key: MechanicEventKind;
 	label: string;
 	description: string;
+	fields?: readonly {
+		path: string;
+		label: string;
+		type: 'boolean' | 'number' | 'string';
+	}[];
 };
 
 export const MECHANIC_EVENT_REGISTRY: Readonly<Record<MechanicEventKind, MechanicEventDefinition>> = {
@@ -36,7 +41,11 @@ export const MECHANIC_EVENT_REGISTRY: Readonly<Record<MechanicEventKind, Mechani
 	weapon_hit: {
 		key: 'weapon_hit',
 		label: 'Weapon hit',
-		description: 'A weapon attack connects with a target. Critical and distance details belong in event values.'
+		description: 'A weapon attack connects with a target. The headshot boolean distinguishes headshots from body shots.',
+		fields: [
+			{ path: 'targetId', label: 'Target ID', type: 'string' },
+			{ path: 'values.headshot', label: 'Headshot', type: 'boolean' }
+		]
 	},
 	skill_deployed: {
 		key: 'skill_deployed',
@@ -326,6 +335,7 @@ export type MechanicOutcomeEmission = {
 	clauseId: string;
 	outcomeId: string;
 	at: number;
+	targetId: string | null;
 	phase: OutcomePhase;
 	kind: MechanicOutcome['kind'];
 	scope: MechanicOutcome['scope'];
@@ -401,6 +411,7 @@ type EvaluationContext = {
 type ContinuousDelivery = {
 	clauseId: string;
 	outcomeId: string;
+	targetId: string | null;
 	phase: OutcomePhase;
 	scope: MechanicOutcomeScope;
 	resource: MechanicResource;
@@ -895,14 +906,22 @@ function emitOutcomes(
 	continuousDeliveries?: ContinuousDelivery[]
 ): MechanicOutcomeEmission[] {
 	const emissions: MechanicOutcomeEmission[] = [];
+	const stateValues = (outcome: MechanicOutcome) => {
+		const current = outcomeState(outcome, context);
+		const previous = outcome.statePool ? before.get(outcome.statePool) ?? current : current;
+		return {
+			current,
+			previous,
+			effective: outcome.phase === 'on_exit' ? previous : current
+		};
+	};
 	const eligible = (clause.outcomes ?? []).filter((outcome) => {
 		if (phase === 'before' && outcome.phase !== 'on_event') return false;
 		if (phase === 'after' && outcome.phase === 'on_event') return false;
-		const current = outcomeState(outcome, context);
-		const previous = outcome.statePool ? before.get(outcome.statePool) ?? current : current;
+		const { current, previous, effective } = stateValues(outcome);
 		if (!phaseMatches(outcome.phase, previous, current)) return false;
-		if (outcome.minStacks !== undefined && current < outcome.minStacks) return false;
-		if (outcome.maxStacks !== undefined && current > outcome.maxStacks) return false;
+		if (outcome.minStacks !== undefined && effective < outcome.minStacks) return false;
+		if (outcome.maxStacks !== undefined && effective > outcome.maxStacks) return false;
 		return true;
 	}).sort((left, right) => {
 		const priority = (outcome: MechanicOutcome) =>
@@ -910,7 +929,7 @@ function emitOutcomes(
 		return priority(left) - priority(right);
 	});
 	for (const outcome of eligible) {
-		const current = outcomeState(outcome, context);
+		const { effective: current } = stateValues(outcome);
 		const baseValue = numericValue(outcome.value, context);
 		const value = outcome.perStack ? baseValue * current : baseValue;
 		const resolvedValue = resolveOutcomeValue(outcome, value, context);
@@ -925,6 +944,7 @@ function emitOutcomes(
 			continuousDeliveries?.push({
 				clauseId: clause.id,
 				outcomeId: outcome.id,
+				targetId: context.event.targetId ?? null,
 				phase: outcome.phase,
 				scope: outcome.scope,
 				resource: outcomeResource(outcome),
@@ -957,6 +977,7 @@ function emitOutcomes(
 			clauseId: clause.id,
 			outcomeId: outcome.id,
 			at,
+			targetId: context.event.targetId ?? null,
 			phase: outcome.phase,
 			kind: outcome.kind,
 			scope: outcome.scope,
@@ -1007,6 +1028,7 @@ function advanceContinuousDeliveries(
 			clauseId: delivery.clauseId,
 			outcomeId: delivery.outcomeId,
 			at: through,
+			targetId: delivery.targetId,
 			phase: delivery.phase,
 			kind: 'restoration',
 			scope: delivery.scope,

src/lib/components/MechanicLanguageHelp.svelte

@@ -40,10 +40,11 @@
 				<div><dt>IF</dt><dd>Conditions checked against the event, Agent, target, team, or encounter.</dd></div>
 				<div><dt>TRACK</dt><dd>A count, duration, scalar, mark, or stack pool shared by branches.</dd></div>
 				<div><dt>ADD / SET / CONSUME</dt><dd>How a matching branch changes tracked state.</dd></div>
+				<div><dt>FOR EVENT TARGET</dt><dd>Binds a target-scoped state change to the enemy named by the event.</dd></div>
 				<div><dt>APPLY</dt><dd>The Attribute or direct result and the phase when it takes effect.</dd></div>
 				<div><dt>UNTIL</dt><dd>The expiry, reset, or transfer policy for tracked state.</dd></div>
 				<div><dt>EVERY</dt><dd>An explicit periodic interval. ISAC does not infer a missing cadence.</dd></div>
-				<div><dt>PHASE</dt><dd>Whether an outcome runs before state changes, after them, or while state remains active.</dd></div>
+				<div><dt>PHASE</dt><dd>Whether an outcome runs before state changes, after them, while state remains active, or when state expires.</dd></div>
 			</dl>
 			<PseudoScript title="MECHANIC EXAMPLE" lines={example} compact />
 			<section class="calculation-language">

src/lib/components/isac/MechanicProgramEditor.svelte

@@ -235,6 +235,7 @@
 		| 'static'
 		| 'event'
 		| 'attribute'
+		| 'attribute_value'
 		| 'reducer'
 		| 'scenario'
 		| 'protocol_upgrades'
@@ -243,6 +244,7 @@
 	const valueModelOptions = $derived([
 		{ value: 'static', label: 'STATIC' },
 		{ value: 'event', label: 'EVENT FIELD' },
+		{ value: 'attribute_value', label: 'LIVE ATTRIBUTE' },
 		{ value: 'attribute', label: 'ATTRIBUTE ÷ 100' },
 		{ value: 'reducer', label: 'REDUCER' },
 		{ value: 'scenario', label: 'SCENARIO' },
@@ -298,6 +300,14 @@
 		};
 	}
 
+	function liveAttributeExpression(value: number, attributeId: string): NumericExpression {
+		return {
+			op: 'multiply',
+			left: value,
+			right: { ref: { source: 'attribute', attributeId } }
+		};
+	}
+
 	function outcomeValueModel(outcome: ConditionalMechanicOutcomeDraft): OutcomeValueModel {
 		if (valueModelOverrides[outcome.key]) return valueModelOverrides[outcome.key];
 		const expression = Object.values(outcome.variants)[0]?.expression;
@@ -313,6 +323,7 @@
 				if (expression.right.ref.source === 'event') return 'event';
 				if (expression.right.ref.source === 'scenario') return 'scenario';
 				if (expression.right.ref.source === 'reducer') return 'reducer';
+				if (expression.right.ref.source === 'attribute') return 'attribute_value';
 			}
 			if (
 				'op' in expression.right
@@ -356,6 +367,15 @@
 
 	function outcomeAttributeReference(outcome: ConditionalMechanicOutcomeDraft) {
 		const expression = Object.values(outcome.variants)[0]?.expression;
+		if (
+			expression
+			&& typeof expression === 'object'
+			&& 'op' in expression
+			&& expression.op === 'multiply'
+			&& typeof expression.right === 'object'
+			&& 'ref' in expression.right
+			&& expression.right.ref.source === 'attribute'
+		) return expression.right.ref.attributeId;
 		if (
 			expression
 			&& typeof expression === 'object'
@@ -380,6 +400,9 @@
 		if (model === 'attribute') return reference
 			? attributePercentExpression(value, reference)
 			: undefined;
+		if (model === 'attribute_value') return reference
+			? liveAttributeExpression(value, reference)
+			: undefined;
 		if (model === 'scenario') return reference
 			? referenceExpression('scenario', reference, value)
 			: undefined;
@@ -398,7 +421,9 @@
 	) {
 		const outcome = rule.clauses[clauseIndex].outcomes[outcomeIndex];
 		const nextOverrides = { ...valueModelOverrides };
-		if (model === 'attribute' && !reference) nextOverrides[outcome.key] = 'attribute';
+		if ((model === 'attribute' || model === 'attribute_value') && !reference) {
+			nextOverrides[outcome.key] = model;
+		}
 		else delete nextOverrides[outcome.key];
 		valueModelOverrides = nextOverrides;
 		const variants = Object.fromEntries(Object.entries(outcome.variants).map(([key, variant]) => {
@@ -442,6 +467,17 @@
 				variants: { base: { value, expression } }
 			}));
 		}
+		if (model === 'attribute_value') {
+			return liveAttributeExpression(value, outcomeAttributeReference({
+				key: 'temporary',
+				label: 'Temporary',
+				phase: 'on_event',
+				kind: 'marker',
+				scope: 'self',
+				basis: 'flat',
+				variants: { base: { value, expression } }
+			}));
+		}
 		if (model === 'reducer') {
 			return { op: 'multiply', left: value, right: { ref: { source: 'reducer' } } };
 		}
@@ -452,8 +488,11 @@
 	function addMutation(clauseIndex: number) {
 		const pool = rule.pools[0]?.key;
 		if (!pool) return;
+		const entity = rule.pools[0]?.scope === 'target'
+			? { kind: 'event_target' as const }
+			: undefined;
 		updateClause(clauseIndex, {
-			mutations: [...rule.clauses[clauseIndex].mutations, { kind: 'add', pool, value: 1 }]
+			mutations: [...rule.clauses[clauseIndex].mutations, { kind: 'add', pool, value: 1, entity }]
 		});
 	}
 
@@ -461,9 +500,25 @@
 		const mutations = [...rule.clauses[clauseIndex].mutations];
 		const current = mutations[mutationIndex];
 		const nextPool = pool ?? ('pool' in current ? current.pool : rule.pools[0]?.key ?? '');
+		const nextPoolDefinition = rule.pools.find((candidate) => candidate.key === nextPool);
+		const entity = nextPoolDefinition?.scope === 'target'
+			? ('entity' in current && current.entity ? current.entity : { kind: 'event_target' as const })
+			: undefined;
 		mutations[mutationIndex] = kind === 'clear'
-			? { kind, pool: nextPool }
-			: { kind, pool: nextPool, value: value ?? ('value' in current && typeof current.value === 'number' ? current.value : 1) };
+			? { kind, pool: nextPool, entity }
+			: { kind, pool: nextPool, value: value ?? ('value' in current && typeof current.value === 'number' ? current.value : 1), entity };
+		updateClause(clauseIndex, { mutations });
+	}
+
+	function updateMutationEntity(
+		clauseIndex: number,
+		mutationIndex: number,
+		kind: 'event_target' | 'event_actor'
+	) {
+		const mutations = [...rule.clauses[clauseIndex].mutations];
+		const mutation = mutations[mutationIndex];
+		if (!('pool' in mutation) || mutation.kind === 'transfer') return;
+		mutations[mutationIndex] = { ...mutation, entity: { kind } };
 		updateClause(clauseIndex, { mutations });
 	}
 
@@ -680,6 +735,15 @@
 							{#if mutation.kind !== 'clear'}
 								<label class="field">VALUE<input type="number" step="any" value={'value' in mutation && typeof mutation.value === 'number' ? mutation.value : 1} oninput={(event) => updateMutation(clauseIndex,mutationIndex,mutation.kind === 'set' || mutation.kind === 'consume' ? mutation.kind : 'add',undefined,Number(event.currentTarget.value))}/></label>
 							{/if}
+							{#if 'pool' in mutation && rule.pools.find((pool) => pool.key === mutation.pool)?.scope === 'target'}
+								<SegmentedChoice
+									legend="STATE OWNER"
+									name={`${idPrefix}-mutation-entity-${clauseIndex}-${mutationIndex}`}
+									options={[{value:'event_target',label:'EVENT TARGET'},{value:'event_actor',label:'EVENT ACTOR'}]}
+									value={'entity' in mutation && mutation.entity?.kind === 'event_actor' ? 'event_actor' : 'event_target'}
+									onchange={(values) => updateMutationEntity(clauseIndex,mutationIndex,values[0] as 'event_target'|'event_actor')}
+								/>
+							{/if}
 							<button type="button" class="remove" onclick={() => updateClause(clauseIndex,{mutations:clause.mutations.filter((_,index) => index !== mutationIndex)})}>REMOVE</button>
 						</div>
 					{:else}
@@ -747,14 +811,14 @@
 								columns={Math.min(4,rule.scenarioInputs.length)}
 								onchange={(values) => setOutcomeValueModel(clauseIndex,outcomeIndex,'scenario',values[0])}
 							/>
-						{:else if outcomeValueModel(outcome) === 'attribute'}
+						{:else if outcomeValueModel(outcome) === 'attribute' || outcomeValueModel(outcome) === 'attribute_value'}
 							<SearchableAssignment
 								items={attributes}
 								mode="single"
 								compact
 								subjectLabel="VALUE ATTRIBUTE"
 								value={outcomeAttributeReference(outcome)}
-								onvaluechange={(value) => setOutcomeValueModel(clauseIndex,outcomeIndex,'attribute',value)}
+								onvaluechange={(value) => setOutcomeValueModel(clauseIndex,outcomeIndex,outcomeValueModel(outcome),value)}
 							/>
 						{/if}
 						{#if rule.pools.length}
@@ -823,7 +887,7 @@
 	.branch-readout{display:grid;align-content:center;gap:3px;min-height:44px;padding:7px 9px;border:1px solid var(--shd-border);background:var(--shd-surface-raised)}.branch-readout span{color:var(--shd-text-muted);font-size:var(--shd-type-telemetry);font-weight:900;letter-spacing:.7px}.branch-readout strong{font-size:var(--shd-type-supporting)}
 	.reducer-controls{display:grid;grid-template-columns:minmax(0,1fr) repeat(2,minmax(130px,.25fr));align-items:end;gap:var(--shd-gap-sm);padding:0 var(--shd-gap-sm) var(--shd-gap-sm)}
 	.mutation-panel{margin:0 var(--shd-gap-sm) var(--shd-gap-sm);border:1px solid var(--shd-border-soft)}
-	.mutation-row{display:grid;grid-template-columns:minmax(300px,1fr) minmax(260px,1fr) minmax(110px,.35fr) auto;align-items:end;gap:8px;padding:8px;border-bottom:1px solid var(--shd-border-soft)}
+	.mutation-row{display:grid;grid-template-columns:minmax(260px,1fr) minmax(220px,1fr) minmax(110px,.35fr) minmax(240px,1fr) auto;align-items:end;gap:8px;padding:8px;border-bottom:1px solid var(--shd-border-soft)}
 	.outcome-card{display:grid;gap:8px;margin:var(--shd-gap-sm);padding:9px;border:1px solid var(--shd-border);border-left:2px solid var(--shd-info);background:var(--shd-surface-raised)}
 	.outcome-grid{display:grid;grid-template-columns:minmax(200px,1fr) minmax(360px,1.4fr) minmax(120px,.3fr);align-items:end;gap:8px}
 	.variant-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:8px}

src/lib/server/ai/mechanic-authoring-prompt.test.ts

@@ -78,7 +78,7 @@ describe('AI mechanic authoring prompt', () => {
 			recipeKeys: []
 		}));
 
-		expect(AI_MECHANIC_PROMPT_VERSION).toBe(4);
+		expect(AI_MECHANIC_PROMPT_VERSION).toBe(5);
 		expect(input.canonicalCatalog.grammar.outcome.optional).toEqual(
 			expect.arrayContaining(['delivery', 'durationSeconds'])
 		);
@@ -115,7 +115,7 @@ describe('AI mechanic authoring prompt', () => {
 			expect.stringContaining('Do not replace continuous delivery with a periodic reducer')
 		]));
 		expect(AI_MECHANIC_AUTHORING_INSTRUCTIONS).toContain(
-			'Prompt contract version: 4'
+			'Prompt contract version: 5'
 		);
 
 		const advertised = structuredClone(
@@ -156,4 +156,89 @@ describe('AI mechanic authoring prompt', () => {
 		});
 		expect(parsed.ok).toBe(true);
 	});
+
+	it('advertises Precise Trauma through target expiry without inventing target tick iteration', () => {
+		const skillDamageId = 'skill-damage-catalog-id';
+		const input = JSON.parse(buildAiMechanicAuthoringInput({
+			request: {
+				...request,
+				context: {
+					...request.context,
+					sourceName: 'Precise Trauma',
+					sourceDescription:
+						'Hits apply a debuff for 1 second, up to 10 stacks. Body shots add 1 stack and headshots add 2 stacks.'
+				}
+			},
+			attributes: [{
+				id: skillDamageId,
+				name: 'Skill Damage',
+				description: null,
+				unit: null,
+				type: null,
+				category: null,
+				calculationType: null
+			}],
+			events: [{ key: 'weapon_hit', label: 'Weapon hit' }],
+			actions: [
+				{ key: 'body_shot', label: 'Body shot' },
+				{ key: 'headshot', label: 'Headshot' }
+			],
+			recipeKeys: ['body_shot', 'headshot']
+		}));
+		const advertised = structuredClone(input.canonicalCatalog.grammar.preciseTraumaShape);
+		const outcome = advertised.clauses[0].outcomes[0];
+		const baseVariant = JSON.parse(JSON.stringify(
+			outcome.variants['replace-with-each-required-variant-key']
+		).replaceAll(
+			'replace-with-the-exact-skill-damage-catalog-id',
+			skillDamageId
+		));
+		outcome.variants = {
+			I: structuredClone(baseVariant),
+			II: structuredClone(baseVariant)
+		};
+
+		expect(advertised.pools[0]).toMatchObject({
+			scope: 'target',
+			max: 10,
+			expiresAfterSeconds: 1
+		});
+		expect(advertised.clauses[0].mutations[0]).toEqual({
+			kind: 'add',
+			pool: 'trauma',
+			entity: { kind: 'event_target' },
+			value: 1
+		});
+		expect(advertised.clauses[1].mutations[0]).toMatchObject({ value: 2 });
+		expect(outcome).toMatchObject({
+			phase: 'on_exit',
+			kind: 'direct_damage',
+			scope: 'target',
+			statePool: 'trauma',
+			perStack: true,
+			variants: {
+				I: {
+					expression: {
+						ref: {
+							source: 'attribute',
+							attributeId: skillDamageId
+						}
+					}
+				}
+			}
+		});
+		expect(input.examplesAndRules).toEqual(expect.arrayContaining([
+			expect.stringContaining('uses the entity previous state'),
+			expect.stringContaining('without inventing generic repeated target ticks')
+		]));
+		expect(JSON.stringify(input.canonicalCatalog.grammar.preciseTraumaShape))
+			.not.toContain('entitiesFromPool');
+
+		const parsed = parseConditionalMechanicDraft(advertised, {
+			variantKeys: ['I', 'II'],
+			allowedAttributeIds: new Set([skillDamageId]),
+			allowedRecipeKeys: new Set(['body_shot', 'headshot'])
+		});
+		expect(parsed.ok).toBe(true);
+	});
 });

src/lib/server/ai/mechanic-authoring-prompt.ts

@@ -2,7 +2,7 @@ import type { AiMechanicAuthoringRequest } from '$lib/ai/mechanic-authoring';
 import { CONDITIONAL_MECHANIC_OUTCOME_CAPABILITIES } from '$lib/calculations/mechanic-editor';
 import type { AiMechanicAttribute } from './mechanic-authoring-context';
 
-export const AI_MECHANIC_PROMPT_VERSION = 4;
+export const AI_MECHANIC_PROMPT_VERSION = 5;
 
 const mechanicsGrammar = {
 	version: 1,
@@ -19,7 +19,9 @@ const mechanicsGrammar = {
 		scope: ['agent', 'target'],
 		optional: ['min', 'max', 'bestCaseValue', 'expiresAfterSeconds'],
 		expirationSemantics:
-			'expiresAfterSeconds is one shared pool timer. Every write to the pool resets that timer for the entire pool, and expiry resets the full pool to its initial value.'
+			'expiresAfterSeconds is one timer per pool entity. Every write resets that entity timer, and expiry resets only that entity to the pool initial value.',
+		targetScopeSemantics:
+			'A target-scoped pool stores one independent value and expiry timer per resolved entity. Use mutation.entity event_target when a weapon-hit mechanic binds state to the enemy that was hit.'
 	},
 	clause: {
 		required: ['key', 'event', 'if', 'reducer', 'mutations', 'outcomes'],
@@ -94,6 +96,12 @@ const mechanicsGrammar = {
 	mutationShapes: [
 		{ kind: 'none' },
 		{ kind: 'add', pool: 'stacks', value: 1 },
+		{
+			kind: 'add',
+			pool: 'target-stacks',
+			entity: { kind: 'event_target' },
+			value: 1
+		},
 		{ kind: 'set', pool: 'active', value: 1 },
 		{ kind: 'consume', pool: 'stacks', value: 1 },
 		{ kind: 'derive', pool: 'nearby-enemies', value: { ref: { source: 'reducer' } } },
@@ -138,6 +146,98 @@ const mechanicsGrammar = {
 			}
 		}
 	},
+	preciseTraumaShape: {
+		version: 1,
+		simulationReadiness: 'ready',
+		scenarioInputs: [],
+		pools: [{
+			key: 'trauma',
+			label: 'Trauma',
+			stateKind: 'stack',
+			scope: 'target',
+			initial: 0,
+			min: 0,
+			max: 10,
+			bestCaseValue: 10,
+			expiresAfterSeconds: 1
+		}],
+		clauses: [
+			{
+				key: 'body-shot-trauma',
+				label: 'Body shot adds one Trauma stack',
+				recipeKey: 'body_shot',
+				event: 'weapon_hit',
+				if: {
+					kind: 'all',
+					predicates: [
+						{ kind: 'exists', value: { source: 'event', path: 'targetId' } },
+						{ kind: 'exists', value: { source: 'event', path: 'values.headshot' } },
+						{
+							kind: 'compare',
+							left: { source: 'event', path: 'values.headshot' },
+							operator: 'eq',
+							right: false
+						}
+					]
+				},
+				reducer: { kind: 'none' },
+				mutations: [{
+					kind: 'add',
+					pool: 'trauma',
+					entity: { kind: 'event_target' },
+					value: 1
+				}],
+				outcomes: [{
+					key: 'trauma-skill-damage',
+					label: 'Trauma Skill Damage',
+					phase: 'on_exit',
+					kind: 'direct_damage',
+					scope: 'target',
+					basis: 'flat',
+					statePool: 'trauma',
+					perStack: true,
+					variants: {
+						'replace-with-each-required-variant-key': {
+							value: 0,
+							expression: {
+								ref: {
+									source: 'attribute',
+									attributeId: 'replace-with-the-exact-skill-damage-catalog-id'
+								}
+							}
+						}
+					}
+				}]
+			},
+			{
+				key: 'headshot-trauma',
+				label: 'Headshot adds two Trauma stacks',
+				recipeKey: 'headshot',
+				event: 'weapon_hit',
+				if: {
+					kind: 'all',
+					predicates: [
+						{ kind: 'exists', value: { source: 'event', path: 'targetId' } },
+						{ kind: 'exists', value: { source: 'event', path: 'values.headshot' } },
+						{
+							kind: 'compare',
+							left: { source: 'event', path: 'values.headshot' },
+							operator: 'eq',
+							right: true
+						}
+					]
+				},
+				reducer: { kind: 'none' },
+				mutations: [{
+					kind: 'add',
+					pool: 'trauma',
+					entity: { kind: 'event_target' },
+					value: 2
+				}],
+				outcomes: []
+			}
+		]
+	},
 	variantValue: {
 		required: ['value'],
 		optional: ['expression']
@@ -241,6 +341,10 @@ export function buildAiMechanicAuthoringInput(input: {
 			'An Attribute whose catalog unit is % resolves to its displayed percentage number, such as 20 for 20%. Divide that reference by 100 when wording applies it as a percentage multiplier, such as 240 × 20%.',
 			'Continuous Health restoration is supported. Use kind:"restoration", resource:"health", delivery:"continuous", and a positive durationSeconds. The variant expression resolves the total restoration across that duration, not a per-second value. Do not replace continuous delivery with a periodic reducer.',
 			'Each continuous-restoration activation creates an independent constant-rate stream. Overlapping streams add, and restoration above the resource maximum is lost when it occurs.',
+			'A target-scoped pool owns an independent value and expiry timer for each entity. Bind hit-created target state with entity:{kind:"event_target"}; do not collapse different enemies into one Agent-scoped pool.',
+			'Writing a target-scoped pool refreshes only that target entity timer. An on_exit outcome runs when that entity expires and uses the entity previous state for stack bands and perStack multiplication, even though the stored pool value has already reset.',
+			'When an outcome value is exactly a live Attribute amount, use the Attribute reference directly as the variant expression. Divide by 100 only when a displayed percentage is being used as a multiplier.',
+			'Precise Trauma is representable as one target-scoped stack pool with a one-second expiry: body shots add one stack, headshots add two, and one on_exit direct-damage outcome uses the expiring target previous stack count. This models the stated one-second debuff without inventing generic repeated target ticks.',
 			'OS Protocol upgrade scaling may use equipment.protocolTalentUpgrades only when allowProtocolUpgradeScaling is true.',
 			'Assigned-ability scope may be used only when allowAssignedAbility is true.',
 			'If cadence is not stated, ask rather than assuming a one-second interval.',

src/lib/server/conditional-effects.test.ts

@@ -182,14 +182,27 @@ describe('conditional mechanic persistence adapter', () => {
 			version: 1,
 			simulationReadiness: 'ready',
 			scenarioInputs: [],
-			pools: [],
+			pools: [{
+				key: 'marked-target',
+				label: 'Marked Target',
+				stateKind: 'target_mark',
+				scope: 'target',
+				initial: 0,
+				min: 0,
+				max: 1
+			}],
 			clauses: [{
 				key: 'weapon-kill',
 				label: 'Weapon kill',
 				event: 'enemy_killed',
 				if: { kind: 'true' },
 				reducer: { kind: 'none' },
-				mutations: [],
+				mutations: [{
+					kind: 'set',
+					pool: 'marked-target',
+					entity: { kind: 'event_target' },
+					value: 1
+				}],
 				outcomes: [{
 					key: 'restore-health',
 					label: 'Restore Health',
@@ -204,6 +217,51 @@ describe('conditional mechanic persistence adapter', () => {
 						I: { value: 240 },
 						II: { value: 336 }
 					}
+				}, {
+					key: 'target-detonation',
+					label: 'Target Detonation',
+					phase: 'on_exit',
+					kind: 'direct_damage',
+					scope: 'target',
+					basis: 'flat',
+					statePool: 'marked-target',
+					perStack: true,
+					variants: {
+						I: {
+							value: 240,
+							expression: {
+								op: 'multiply',
+								left: 240,
+								right: {
+									op: 'divide',
+									left: {
+										ref: {
+											source: 'attribute',
+											attributeId: '82a95611-283b-4fd8-a6ed-3567a316f36e'
+										}
+									},
+									right: 100
+								}
+							}
+						},
+						II: {
+							value: 336,
+							expression: {
+								op: 'multiply',
+								left: 336,
+								right: {
+									op: 'divide',
+									left: {
+										ref: {
+											source: 'attribute',
+											attributeId: '82a95611-283b-4fd8-a6ed-3567a316f36e'
+										}
+									},
+									right: 100
+								}
+							}
+						}
+					}
 				}]
 			}]
 		});
@@ -213,7 +271,9 @@ describe('conditional mechanic persistence adapter', () => {
 		)).all();
 		expect(saved).toEqual([
 			{ delivery_mode: 'continuous', delivery_duration_seconds: 3 },
-			{ delivery_mode: 'continuous', delivery_duration_seconds: 3 }
+			{ delivery_mode: 'instant', delivery_duration_seconds: null },
+			{ delivery_mode: 'continuous', delivery_duration_seconds: 3 },
+			{ delivery_mode: 'instant', delivery_duration_seconds: null }
 		]);
 		const loaded = await loadConditionalRuleDraft(
 			database,
@@ -229,5 +289,39 @@ describe('conditional mechanic persistence adapter', () => {
 				II: { value: 336 }
 			}
 		});
+		expect(loaded?.pools[0]).toMatchObject({
+			key: 'marked-target',
+			stateKind: 'target_mark',
+			scope: 'target'
+		});
+		expect(loaded?.clauses[0].mutations).toEqual([{
+			kind: 'set',
+			pool: 'marked-target',
+			entity: { kind: 'event_target' },
+			value: 1
+		}]);
+		expect(loaded?.clauses[0].outcomes[1]).toMatchObject({
+			phase: 'on_exit',
+			kind: 'direct_damage',
+			scope: 'target',
+			statePool: 'marked-target',
+			perStack: true,
+			variants: {
+				I: {
+					value: 240,
+					expression: expect.objectContaining({
+						right: expect.objectContaining({
+							left: {
+								ref: {
+									source: 'attribute',
+									attributeId: '82a95611-283b-4fd8-a6ed-3567a316f36e'
+								}
+							}
+						})
+					})
+				},
+				II: { value: 336 }
+			}
+		});
 	});
 });

src/routes/isac/mechanic-reference/+page.svelte

@@ -88,7 +88,7 @@
 	];
 
 	const mutations = [
-		{ syntax: 'ADD value TO pool', use: 'Increases state, respecting the pool maximum.' },
+		{ syntax: 'ADD value TO pool FOR EVENT TARGET', use: 'Increases one enemy’s target-scoped state, respecting the pool maximum.' },
 		{ syntax: 'SET value AS pool', use: 'Replaces the current pool value.' },
 		{ syntax: 'CONSUME value FROM pool', use: 'Spends available state without falling below the pool minimum.' },
 		{ syntax: 'CLEAR pool', use: 'Resets the selected state pool.' },
@@ -99,7 +99,7 @@
 		{ syntax: 'ON_EVENT', use: 'Applies against combat state as the event arrives.' },
 		{ syntax: 'AFTER_EVENT', use: 'Applies after branch mutations and resource costs.' },
 		{ syntax: 'ON_ENTER', use: 'Applies when tracked state enters an active range.' },
-		{ syntax: 'ON_EXIT', use: 'Applies when tracked state leaves an active range.' },
+		{ syntax: 'ON_EXIT', use: 'Applies when tracked state leaves an active range, using its final pre-exit value for stack thresholds and scaling.' },
 		{ syntax: 'WHILE_ACTIVE', use: 'Remains active while the referenced state satisfies its stack range.' }
 	];
 
@@ -155,6 +155,22 @@
 		'ON_EVENT: APPLY 2 CURRENT_HEALTH_PERCENT // Health cost',
 		'AFTER_EVENT: APPLY (0.6 * (1 + (EQUIPMENT.protocolTalentUpgrades / 5))) CURRENT_HEALTH_PERCENT USING CURRENT HEALTH // Additional damage'
 	];
+
+	const preciseTrauma = [
+		'MECHANIC PRECISE TRAUMA',
+		'STATE trauma [TARGET] 0..10; EXPIRES 1s AFTER WRITE',
+		'',
+		'WHEN WEAPON HIT // Body shot',
+		'IF EVENT.targetId EXISTS AND EVENT.values.headshot == false',
+		'ADD 1 TO trauma FOR EVENT TARGET',
+		'',
+		'WHEN WEAPON HIT // Headshot',
+		'IF EVENT.targetId EXISTS AND EVENT.values.headshot == true',
+		'ADD 2 TO trauma FOR EVENT TARGET',
+		'',
+		'WHEN SIMULATION TICK // Shared refreshed expiry',
+		'ON_EXIT: APPLY (1 * ATTRIBUTE[skill-damage-id]) FLAT DIRECT_DAMAGE PER STACK TO EVENT TARGET'
+	];
 </script>
 
 <svelte:head>
@@ -210,6 +226,13 @@
 					<article>
 						<div><strong>{event.label}</strong><code>{event.key}</code></div>
 						<p>{event.description}</p>
+						{#if event.fields?.length}
+							<ul aria-label={`${event.label} typed fields`}>
+								{#each event.fields as field}
+									<li><code>{field.path}</code><span>{field.label} · {field.type.toUpperCase()}</span></li>
+								{/each}
+							</ul>
+						{/if}
 					</article>
 				{/each}
 			</div>
@@ -318,7 +341,7 @@
 			</div>
 			<aside class="contract">
 				<strong>EXPIRY CONTRACT</strong>
-				<span>A pool can expire after its last write. A new stack refreshes that timer when the mechanic defines refresh-on-write behavior.</span>
+				<span>A pool can expire after its last write. Each write refreshes its timer. Target pools maintain independent values and timers for each bound enemy.</span>
 			</aside>
 		</section>
 
@@ -376,6 +399,10 @@
 		<section id="examples" class="reference-section examples-section">
 			<header><div><span>10</span><h3>WORKED MECHANICS</h3></div></header>
 			<div class="example-intro">
+				<div>
+					<h4>PRECISE TRAUMA</h4>
+					<p>Body shots add one target-bound stack and headshots add two. Each hit refreshes that enemy’s shared one-second expiry; the expiry deals one live Skill Damage value per final stack.</p>
+				</div>
 				<div>
 					<h4>SUPERIOR FIREPOWER</h4>
 					<p>Nine hits on one target add a Relentless stack. Each write refreshes the ten-second pool timer.</p>
@@ -386,6 +413,7 @@
 				</div>
 			</div>
 			<div class="example-scripts">
+				<PseudoScript title="PRECISE TRAUMA · GENERATED EXAMPLE" lines={preciseTrauma} readiness="READY" />
 				<PseudoScript title="SUPERIOR FIREPOWER · GENERATED EXAMPLE" lines={superiorFirepower} readiness="READY" />
 				<PseudoScript title="HAPPY SURVIVAL · GENERATED EXAMPLE" lines={happySurvival} readiness="REQUIRES ASSUMPTIONS" />
 			</div>
@@ -652,6 +680,25 @@
 		line-height: 1.45;
 	}
 
+	.event-registry ul {
+		display: grid;
+		gap: 4px;
+		margin: 2px 0 0;
+		padding: 0;
+		list-style: none;
+	}
+
+	.event-registry li {
+		display: flex;
+		flex-wrap: wrap;
+		justify-content: space-between;
+		gap: 6px;
+		padding-top: 5px;
+		border-top: 1px solid var(--shd-border-soft);
+		color: var(--shd-text-muted);
+		font-size: var(--shd-type-telemetry);
+	}
+
 	.action-registry {
 		display: grid;
 		grid-template-columns: repeat(3, minmax(0, 1fr));
@@ -937,7 +984,7 @@
 
 	.example-scripts {
 		display: grid;
-		grid-template-columns: repeat(2, minmax(0, 1fr));
+		grid-template-columns: repeat(3, minmax(0, 1fr));
 		gap: 8px;
 		padding: 0 12px 12px;
 	}

src/routes/isac/talents/+page.server.ts

@@ -219,28 +219,33 @@ export const actions: Actions = {
 			valueII: effect.variants.II.value
 		}));
 		const validationErrors: TalentValidationError[] = [];
+		const requiresCompleteMechanic = conditionalRule.simulationReadiness !== 'captured_only';
 		if (name.length < 2 || !['Weapon Talent 1', 'Weapon Talent 2', 'Backpack', 'Body Armor'].includes(category)) {
 			validationErrors.push({ area: 'identity', message: 'Provide a valid talent name and category. Exotic talents are managed from their owning weapon.' });
 		}
 		if (!descriptionTemplate) validationErrors.push({ area: 'description', message: 'Enter a shared description template.' });
-		if (!conditionalRule.clauses.length) validationErrors.push({ area: 'mechanic', message: 'Add at least one mechanic branch.' });
-		if (!sharedEffects.length) validationErrors.push({ area: 'outcomes', message: 'Add at least one numbered value outcome.' });
+		if (requiresCompleteMechanic && !conditionalRule.clauses.length) {
+			validationErrors.push({ area: 'mechanic', message: 'Add at least one mechanic branch or mark the talent CAPTURE ONLY.' });
+		}
+		if (requiresCompleteMechanic && !sharedEffects.length) {
+			validationErrors.push({ area: 'outcomes', message: 'Add at least one numbered value outcome or mark the talent CAPTURE ONLY.' });
+		}
 		if (sharedEffects.some((effect) => !Number.isFinite(effect.valueI) || !Number.isFinite(effect.valueII))) {
 			validationErrors.push({ area: 'outcomes', message: 'Every numbered outcome needs valid Tier I and Tier II values.' });
 		}
 		const missingSlots = missingTalentDescriptionSlots(descriptionTemplate, descriptionOutcomes);
-		if (missingSlots.length) {
+		if (requiresCompleteMechanic && missingSlots.length) {
 			validationErrors.push({
 				area: 'description',
 				message: `Description placeholder${missingSlots.length === 1 ? '' : 's'} ${missingSlots.map((slot) => `{${slot}}`).join(', ')} must reference numbered outcomes.`
 			});
 			validationErrors.push({ area: 'outcomes', message: 'Add or renumber outcomes to match every numbered description placeholder.' });
 		}
-		if (descriptionTemplate.includes('{duration}') && durationSeconds === null) {
+		if (requiresCompleteMechanic && descriptionTemplate.includes('{duration}') && durationSeconds === null) {
 			validationErrors.push({ area: 'description', message: 'The description uses {duration}, but no duration is defined.' });
 			validationErrors.push({ area: 'mechanic', message: 'Define a duration for the {duration} description placeholder.' });
 		}
-		if (descriptionTemplate.includes('{max_stacks}') && maxStacks === null) {
+		if (requiresCompleteMechanic && descriptionTemplate.includes('{max_stacks}') && maxStacks === null) {
 			validationErrors.push({ area: 'description', message: 'The description uses {max_stacks}, but no maximum stack count is defined.' });
 			validationErrors.push({ area: 'mechanic', message: 'Define a pool maximum for the {max_stacks} description placeholder.' });
 		}

src/routes/isac/talents/+page.svelte

@@ -42,28 +42,9 @@
 		simulationReadiness: 'captured_only',
 		scenarioInputs: [],
 		pools: [],
-		clauses: [{
-			key: 'primary',
-			label: 'Primary',
-			event: 'weapon_hit',
-			if: { kind: 'true' },
-			reducer: { kind: 'none' },
-			mutations: [],
-			outcomes: [{
-				key: 'effect-1',
-				label: 'Effect 1',
-				phase: 'while_active',
-				kind: 'attribute_modifier',
-				scope: 'equipped_weapon',
-				attributeId: '',
-				basis: 'flat',
-				perStack: false,
-				descriptionSlot: 1,
-				variants: { I: { value: 0 }, II: { value: 0 } }
-			}]
-		}]
+		clauses: []
 	});
-	const blankTalent = () => ({ id: '', name: '', iconUrl: '', category: 'Weapon Talent 1', descriptionTemplate: '', tierIDescription: '', tierIIDescription: '', conditionalRule: blankRule() });
+	const blankTalent = () => ({ id: '', name: '', iconUrl: '', category: 'Weapon Talent 1', descriptionTemplate: '', tierIDescription: '', tierIIDescription: '', conditionalRule: blankRule(), modelingOpen: false });
 	const editTalent = (row: any) => {
 		const tier = (name: string) => row.tiers.find((item: any) => item.tier === name) ?? { description: '', effects: [] };
 		const one = tier('I'), two = tier('II');
@@ -72,7 +53,8 @@
 			descriptionTemplate: row.descriptionTemplate || one.description,
 			tierIDescription: one.description,
 			tierIIDescription: two.description,
-			conditionalRule: row.conditionalRule ?? blankRule()
+			conditionalRule: row.conditionalRule ?? blankRule(),
+			modelingOpen: Boolean(row.conditionalRule?.clauses?.length)
 		};
 	};
 	const configured = (tiers: Array<{ tier: unknown }>, name: string) => tiers.some((item) => item.tier === name);
@@ -105,6 +87,7 @@
 			if (form.talentMode === 'add') iconResetToken += 1;
 			talent = form.talentMode === 'add' ? blankTalent() : null;
 		} else if (talentErrors.length) {
+			if (hasErrors(['mechanic', 'outcomes'])) talent.modelingOpen = true;
 			void tick().then(() => validationSummary?.focus());
 		}
 	});
@@ -143,20 +126,26 @@
 			</div>
 			<label id="talent-description" class="field template-field" class:validation-area-error={hasErrors(['description'])}>SHARED DESCRIPTION TEMPLATE<textarea name="descriptionTemplate" bind:value={talent.descriptionTemplate} placeholder={'Hitting an enemy {1} times grants +{2} for {duration}...'} required aria-invalid={hasErrors(['description']) ? 'true' : undefined}></textarea><small>Use {'{1}'}, {'{2}'}, and so on for effect values. Use {'{duration}'} and {'{max_stacks}'} for defined mechanics. Cooldown is displayed separately.</small>{#each errorsFor('description') as error}<small class="field-error">{error.message}</small>{/each}</label>
 			<div class="tier-preview"><div><span>TIER I PREVIEW</span><p>{preview('I') || 'Description preview'}</p></div><div><span>TIER II PREVIEW</span><p>{preview('II') || 'Description preview'}</p></div></div>
-			<div id="talent-mechanic" class:validation-area-error={hasErrors(['mechanic', 'outcomes'])}>
-				<MechanicProgramEditor
-					attributes={data.stats}
-					valueColumns={[{key:'tierI',variantKey:'I',label:'TIER I'},{key:'tierII',variantKey:'II',label:'TIER II'}]}
-					idPrefix={`talent-${talent.id || 'new'}`}
-					aiContext={{
-						sourceKind: 'talent',
-						sourceName: talent?.name ?? '',
-						sourceDescription: talent?.descriptionTemplate ?? ''
-					}}
-					bind:rule={talent.conditionalRule}
-				/>
-				{#each [...errorsFor('mechanic'), ...errorsFor('outcomes')] as error}<small class="field-error mechanic-field-error">{error.message}</small>{/each}
-			</div>
+			<details id="talent-mechanic" class="modeling-disclosure" class:validation-area-error={hasErrors(['mechanic', 'outcomes'])} bind:open={talent.modelingOpen}>
+				<summary>
+					<span><b>COMBAT MODELING</b><small>{talent.conditionalRule.simulationReadiness === 'captured_only' ? 'CAPTURE ONLY · MODEL LATER' : `${talent.conditionalRule.clauses.length} CONFIGURED ${talent.conditionalRule.clauses.length === 1 ? 'BRANCH' : 'BRANCHES'}`}</small></span>
+					<strong>{talent.modelingOpen ? 'COLLAPSE' : 'EXPAND'}</strong>
+				</summary>
+				<div class="modeling-content">
+					<MechanicProgramEditor
+						attributes={data.stats}
+						valueColumns={[{key:'tierI',variantKey:'I',label:'TIER I'},{key:'tierII',variantKey:'II',label:'TIER II'}]}
+						idPrefix={`talent-${talent.id || 'new'}`}
+						aiContext={{
+							sourceKind: 'talent',
+							sourceName: talent?.name ?? '',
+							sourceDescription: talent?.descriptionTemplate ?? ''
+						}}
+						bind:rule={talent.conditionalRule}
+					/>
+					{#each [...errorsFor('mechanic'), ...errorsFor('outcomes')] as error}<small class="field-error mechanic-field-error">{error.message}</small>{/each}
+				</div>
+			</details>
 			<div class="form-actions"><button type="button" class="secondary" onclick={() => talent = null}>CANCEL</button><button class="primary">SAVE TALENT →</button></div>
 		</PendingForm>
 	</div>