feat(councils): add scaffold prompt hooks and checked-in scaffold files

src/config/schema.ts

@@ -863,6 +863,8 @@ const agentConfigsSchema = z.record(z.string(), agentConfigEntrySchema).default(
 const councilsGroupConfigSchema = z.object({
   arbiter_agent: z.string().min(1),
   freethinker_agent: z.string().min(1),
+  grounder_agent: z.string().min(1).optional(),
+  writer_agent: z.string().min(1).optional(),
   group_prompt_prefix: z.string().min(1),
   novelty_bias: z.enum(['low', 'medium', 'high']).default('medium'),
   risk_tolerance: z.enum(['low', 'medium', 'high']).default('medium'),
@@ -883,6 +885,7 @@ const councilsSchema = z.object({
   }).default({}),
   strict_grounding: z.boolean().default(false),
   strict_meta_validation: z.boolean().default(true),
+  scaffold_path: z.string().optional(),
   groups: z.object({
     D: councilsGroupConfigSchema.default({
       arbiter_agent: 'council_d_arbiter',
@@ -910,6 +913,7 @@ const councilsSchema = z.object({
     }),
   }).default({}),
   meta_arbiter_agent: z.string().min(1).default('council_meta_arbiter'),
+  meta_writer_agent: z.string().min(1).optional(),
 }).default({});
 
 const routingSchema = z.object({

src/councils/orchestrator.ts

@@ -2,6 +2,7 @@ import type { AgentConfigRegistry } from '../agents/registry.js';
 import type { AgentOrchestrator } from '../backends/native/orchestrator.js';
 import type { ModelTier } from '../models/router.js';
 import type { TokenUsage } from '../models/types.js';
+import type { CouncilScaffold } from './scaffold.js';
 import {
   COUNCIL_PIPELINE_VERSION,
   COUNCIL_SCHEMA_VERSION,
@@ -60,11 +61,15 @@ export interface CouncilsConfig {
     P: CouncilGroupConfig;
   };
   meta_arbiter_agent: string;
+  meta_writer_agent?: string;
+  scaffold_path?: string;
 }
 
 interface CouncilGroupConfig {
   arbiter_agent: string;
   freethinker_agent: string;
+  grounder_agent?: string;
+  writer_agent?: string;
   group_prompt_prefix: string;
   novelty_bias: 'low' | 'medium' | 'high';
   risk_tolerance: 'low' | 'medium' | 'high';
@@ -223,16 +228,19 @@ export class CouncilsOrchestrator {
   private readonly _registry: AgentConfigRegistry;
   private readonly _delegateRunner: DelegateRunner;
   private readonly _config: CouncilsConfig;
+  private readonly _scaffold?: CouncilScaffold;
   private readonly _trace: CouncilTraceEvent[] = [];
 
   constructor(deps: {
     registry: AgentConfigRegistry;
     orchestrator: DelegateRunner;
     config: CouncilsConfig;
+    scaffold?: CouncilScaffold;
   }) {
     this._registry = deps.registry;
     this._delegateRunner = deps.orchestrator;
     this._config = deps.config;
+    this._scaffold = deps.scaffold;
   }
 
   async run(rawInput: unknown): Promise<CouncilRunResult> {
@@ -386,12 +394,14 @@ export class CouncilsOrchestrator {
     round?: number;
     promptPayload: unknown;
     modeDirective: string;
+    scaffoldPrompt?: string;
     maxTokens?: number;
   }): Promise<AgentCallResult> {
     const agent = this.getAgent(opts.agentName);
     const message = canonicalStringify(opts.promptPayload);
     const promptHash = hashCanonical(opts.promptPayload);
-    const systemPrompt = `${agent.systemPrompt}\n\n${opts.modeDirective}`;
+    const scaffoldPrompt = opts.scaffoldPrompt ? `${opts.scaffoldPrompt}\n\n` : '';
+    const systemPrompt = `${scaffoldPrompt}${agent.systemPrompt}\n\n${opts.modeDirective}`;
 
     const result = await this._delegateRunner.delegate({
       tier: agent.tier,
@@ -451,6 +461,7 @@ export class CouncilsOrchestrator {
       round,
       promptPayload: ideationPayload,
       modeDirective: 'Return JSON only: {"ideas":[IdeaContent,...]}. Do not include IDs. No prose.',
+      scaffoldPrompt: this._scaffold?.prompts[group].free_thinker,
     });
 
     const ideaOutput = parseJsonWithRepair(ideation.content, (value) => ideationOutputSchema.parse(value));
@@ -482,6 +493,7 @@ export class CouncilsOrchestrator {
       promptPayload: assessmentPayload,
       modeDirective:
         'Return JSON only. Assess provided idea IDs only. No new IDs. Include convergence_signal/novelty_score/repetition_rate.',
+      scaffoldPrompt: this._scaffold?.prompts[group].arbiter,
     });
 
     const assessmentOutput = parseJsonWithRepair(assessmentRaw.content, (value) => assessmentOutputSchema.parse(value));
@@ -524,11 +536,12 @@ export class CouncilsOrchestrator {
       constraints: input.constraints,
     };
 
+    const groundingAgent = groupConfig.grounder_agent ?? groupConfig.freethinker_agent;
     let groundingFailures = 0;
     let grounding = { grounded: [] as Array<{ idea_id: string; mve: string; constraints: string[]; falsifiability_checks: string[] }> };
     try {
       const groundingRaw = await this.callAgent({
-        agentName: groupConfig.freethinker_agent,
+        agentName: groundingAgent,
         callId: `${group}.r${round}.ft.ground`,
         phaseIndex: phaseBase + 2,
         group,
@@ -536,6 +549,7 @@ export class CouncilsOrchestrator {
         promptPayload: groundingPayload,
         modeDirective:
           'Grounder mode. Return JSON only: {"grounded":[{"idea_id", "mve", "constraints", "falsifiability_checks"}]}. No prose.',
+        scaffoldPrompt: this._scaffold?.prompts[group].grounder ?? this._scaffold?.prompts[group].free_thinker,
       });
       grounding = parseJsonWithRepair(groundingRaw.content, (value) => groundingOutputSchema.parse(value));
     } catch {
@@ -686,6 +700,7 @@ export class CouncilsOrchestrator {
       promptPayload: payload,
       modeDirective:
         'Return JSON only following schema with selected_primary/selected_secondary/merges/rejections/open_questions/next_experiments. Use only known idea IDs.',
+      scaffoldPrompt: this._scaffold?.prompts.meta_arbiter,
     });
 
     return parseJsonWithRepair(metaRaw.content, (value) => metaSelectionSchema.parse(value));

src/councils/scaffold.ts

@@ -0,0 +1,37 @@
+import { readFileSync } from 'fs';
+import { z } from 'zod';
+
+const councilPromptSetSchema = z.object({
+  arbiter: z.string().min(1),
+  free_thinker: z.string().min(1),
+  grounder: z.string().min(1).optional(),
+  writer: z.string().min(1).optional(),
+}).strict();
+
+export const councilScaffoldSchema = z.object({
+  generated_at: z.string().optional(),
+  version: z.string().optional(),
+  prompts: z.object({
+    D: councilPromptSetSchema,
+    P: councilPromptSetSchema,
+    meta_arbiter: z.string().min(1),
+  }).strict(),
+}).strict();
+
+export type CouncilScaffold = z.infer<typeof councilScaffoldSchema>;
+
+export function loadCouncilScaffold(path: string): CouncilScaffold {
+  const raw = readFileSync(path, 'utf8');
+  return councilScaffoldSchema.parse(JSON.parse(raw));
+}
+
+export function loadCouncilScaffoldSafe(path?: string): CouncilScaffold | undefined {
+  if (!path) {
+    return undefined;
+  }
+  try {
+    return loadCouncilScaffold(path);
+  } catch {
+    return undefined;
+  }
+}