smarter context assembly implementation

packages/orchestration-service/src/chat/index.js

@@ -7,7 +7,7 @@ const appSettings = require("../config/settings");
 const {triggerSummary} = require('../services/summarization')
 const graph = require('../services/graph');
 
-function buildPrompt(recentEpisodes, semanticEpisodes, neighborhood, userMessage, systemPrompt) {
+function buildPrompt(guaranteed, selected, neighborhood, userMessage, systemPrompt) {
     const parts = [systemPrompt ?? ORCHESTRATION.SYSTEM_PROMPT];
 
     const graphText = formatGraphContext(neighborhood.nodes ?? [], neighborhood.edges ?? []);
@@ -17,17 +17,17 @@ function buildPrompt(recentEpisodes, semanticEpisodes, neighborhood, userMessage
         parts.push("---");
     }
 
-  if (semanticEpisodes.length > 0) {
-    parts.push("Long-term memory (semantically relevant to this message):");
-    for (const ep of semanticEpisodes) {
+  if (selected.length > 0) {
+    parts.push("Relevant memories from earlier conversations:");
+    for (const ep of selected) {
       parts.push(`User: ${ep.user_message}\nAssistant: ${ep.ai_response}`);
     }
     parts.push("---");
   }
 
-  if (recentEpisodes.length > 0) {
+  if (guaranteed.length > 0) {
     parts.push("Recent conversation history (most recent exchanges):");
-    for (const ep of recentEpisodes) {
+    for (const ep of guaranteed) {
       parts.push(`User: ${ep.user_message}\nAssistant: ${ep.ai_response}`);
     }
     parts.push("--- End of recent memories ---\n");
@@ -152,6 +152,7 @@ async function getFTSResults(userMessage, { limit, sessionIds }) {
     }
 }
 
+// Returns {episode, score}[] — scores needed for buildScoredPool downstream
 function fuseEpisodeResults(semanticEps, keywordEps, { semanticWeight, keywordWeight, limit }) {
     const k = RETRIEVAL.RRF_K;
     const scores = new Map();
@@ -164,22 +165,80 @@ function fuseEpisodeResults(semanticEps, keywordEps, { semanticWeight, keywordWe
         const contrib = keywordWeight / (k + i + 1);
         if (scores.has(ep.id)) {
             scores.get(ep.id).score += contrib;
-        } else {
+        } else if (contrib > 0) {
             scores.set(ep.id, { episode: ep, score: contrib });
         }
     });
 
     return [...scores.values()]
         .sort((a, b) => b.score - a.score)
-        .slice(0, limit)
-        .map(({ episode }) => episode);
+        .slice(0, limit);
+
 }
 
+function estimateTokens(episode) {
+    return episode.token_count
+        ?? Math.ceil((episode.user_message.length + episode.ai_response.length) / 4);
+}
+
+function buildScoredPool(fusedWithScores, recentEpisodes, entityBoostedIds, { entityWeight }) {
+    const k = RETRIEVAL.RRF_K;
+    const pool = new Map(); // episode.id → {episode, score}
+
+    for (const { episode, score } of fusedWithScores) {
+        pool.set(episode.id, { episode, score });
+    }
+
+    recentEpisodes.forEach((ep, i) => {
+        const recencyScore = 1.0 / (k + i + 1);
+        if (pool.has(ep.id)) {
+            pool.get(ep.id).score += recencyScore;
+        } else {
+            pool.set(ep.id, { episode: ep, score: recencyScore });
+        }
+    });
+
+    for (const id of entityBoostedIds) {
+        if (pool.has(id)) pool.get(id).score += entityWeight;
+    }
+
+    return [...pool.values()].sort((a, b) => b.score - a.score);
+}
+
+function selectWithinBudget(scoredPool, contextBudget, minRecentEpisodes, recentEpisodes) {
+    let budget = contextBudget;
+    const sortByTime = (a, b) => a.created_at - b.created_at;
+
+    // Guarantee floor: always include the N most recent episodes
+    const guaranteed = recentEpisodes.slice(0, minRecentEpisodes);
+    const guaranteedIds = new Set(guaranteed.map(ep => ep.id));
+    for (const ep of guaranteed) budget -= estimateTokens(ep);
+
+    // Fill remaining budget from scored pool, highest-priority first
+    const selected = [];
+    for (const { episode } of scoredPool) {
+        if (guaranteedIds.has(episode.id)) continue;
+        const cost = estimateTokens(episode);
+
+        // // Break rather than skip — lower-priority episodes aren't worth fitting over higher-priority ones
+        if (budget - cost < 0) break;
+        selected.push(episode);
+        budget -= cost;
+    }
+
+    return {
+        guaranteed: [...guaranteed].sort(sortByTime),
+        selected:   selected.sort(sortByTime),
+    };
+}
+
+
 async function getFusedEpisodes(userMessage, session, recentIds, projectSessionIds, settings) {
     const { semanticLimit, scoreThreshold, semanticWeight, keywordWeight } = settings;
     const ftsSessionIds = projectSessionIds ?? [session.id];
 
     const ftsPromise = keywordWeight > 0
+        //  FTS and semantic may have significant overlap, so fetching more from FTS gives the fusion step more to work with before deduplication.
         ? getFTSResults(userMessage, { limit: semanticLimit * 2, sessionIds: ftsSessionIds })
         : Promise.resolve([]);
 
@@ -194,8 +253,10 @@ async function getFusedEpisodes(userMessage, session, recentIds, projectSessionI
 
 async function assembleContext(externalId, userMessage) {
     const settings = appSettings.load();
-    const { recentEpisodeLimit, semanticLimit, scoreThreshold, 
-            temperature, repeatPenalty, topP, topK, systemPrompt, semanticWeight, keywordWeight } = settings;
+    const { recentEpisodeLimit, semanticLimit, scoreThreshold,
+            temperature, repeatPenalty, topP, topK, systemPrompt,
+            semanticWeight, keywordWeight,
+            contextBudget, entityWeight, minRecentEpisodes } = settings;
 
     // 1. Resolve or create session
     let session = await memory.getSessionByExternalId(externalId);
@@ -222,24 +283,41 @@ async function assembleContext(externalId, userMessage) {
     const isFirstMessage = recentEpisodes.length === 0;
     const recentIds = new Set(recentEpisodes.map(e => e.id));
 
-    // 4. Semantic + entity search
-    const fusedEpisodes = await getFusedEpisodes(userMessage, session, recentIds, projectSessionIds, { semanticLimit, scoreThreshold, semanticWeight, keywordWeight });
-    const entityResults = await getRelevantEntities(userMessage, session.project_id ?? null);
+    // 4. Fused retrieval + entity search in parallel (both are independent)
+    const [fusedWithScores, entityResults] = await Promise.all([
+        getFusedEpisodes(userMessage, session, recentIds, projectSessionIds, { semanticLimit, scoreThreshold, semanticWeight, keywordWeight }),
+        getRelevantEntities(userMessage, session.project_id ?? null),
+    ]);
 
-    // 5. Expand matched entities into 1-hop graph neighborhood
-    let neighborhood = { nodes: [], edges: [] };
-    if (entityResults.length > 0) {
+    // 5. Entity-linked episode IDs for scoring bonus
+    const entityIds = entityResults.map(e => e.id);
+    let entityBoostedIds = new Set();
+    if (entityIds.length > 0) {
         try {
-            neighborhood = await graph.getNeighbors(entityResults.map(e => e.id));
+            const result = await memory.getEpisodesByEntities(entityIds);
+            entityBoostedIds = new Set(result.episodeIds);
+        } catch (err) {
+            logger.debug('[orchestration] Entity-episode lookup failed, skipping bonus:', err.message);
+        }
+    }
+
+    // 6. Build unified scored pool and select within token budget
+    const scoredPool = buildScoredPool(fusedWithScores, recentEpisodes, entityBoostedIds, { entityWeight });
+    const { guaranteed, selected } = selectWithinBudget(scoredPool, contextBudget, minRecentEpisodes, recentEpisodes);
+
+    // 7. Graph neighborhood expansion
+    let neighborhood = { nodes: [], edges: [] };
+    if (entityIds.length > 0) {
+        try {
+            neighborhood = await graph.getNeighbors(entityIds);
         } catch (err) {
             logger.warn('[orchestration] Graph neighborhood fetch failed, falling back to flat entities:', err.message);
-            // Graceful fallback: use Qdrant payload data as flat nodes, no edges
             neighborhood = { nodes: entityResults, edges: [] };
         }
     }
 
-    // 6. Assemble prompt
-    const prompt = buildPrompt(recentEpisodes, fusedEpisodes, neighborhood, userMessage, activeSystemPrompt);
+    // 8. Assemble prompt
+    const prompt = buildPrompt(guaranteed, selected, neighborhood, userMessage, activeSystemPrompt);
 
     return {
         session,

packages/orchestration-service/src/config/settings.js

@@ -16,6 +16,9 @@ const DEFAULTS = {
   systemPrompt:         ORCHESTRATION.SYSTEM_PROMPT,
   semanticWeight:       RETRIEVAL.SEMANTIC_WEIGHT,
   keywordWeight:        RETRIEVAL.KEYWORD_WEIGHT,
+  contextBudget:        ORCHESTRATION.CONTEXT_BUDGET,
+  entityWeight:         ORCHESTRATION.ENTITY_WEIGHT,
+  minRecentEpisodes:    ORCHESTRATION.MIN_RECENT_EPISODES,
 };
 
 function load() {

packages/orchestration-service/src/routes/settings.js

@@ -94,6 +94,27 @@ if (req.body.systemPrompt !== undefined) {
     updates.keywordWeight = val;
   }
 
+  if (req.body.contextBudget !== undefined) {
+    const val = Number(req.body.contextBudget);
+    if (!Number.isInteger(val) || val < 512 || val > 32768)
+        return res.status(400).json({ error: 'contextBudget must be 512–32768' });
+    updates.contextBudget = val;
+  }
+
+  if (req.body.entityWeight !== undefined) {
+      const val = Number(req.body.entityWeight);
+      if (isNaN(val) || val < 0 || val > 2)
+          return res.status(400).json({ error: 'entityWeight must be 0–2' });
+      updates.entityWeight = val;
+  }
+
+  if (req.body.minRecentEpisodes !== undefined) {
+      const val = Number(req.body.minRecentEpisodes);
+      if (!Number.isInteger(val) || val < 0 || val > 10)
+          return res.status(400).json({ error: 'minRecentEpisodes must be 0–10' });
+      updates.minRecentEpisodes = val;
+  }
+
   res.json(settings.save(updates));
 });
 

packages/orchestration-service/src/services/memory.js

@@ -206,6 +206,16 @@ async function searchEpisodes(query, { limit = 10, sessionIds = null } = {}) {
     return res.json();
 }
 
+async function getEpisodesByEntities(entityIds) {
+    const res = await fetch(`${BASE_URL}/episodes/by-entities`, {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ entityIds }),
+    });
+    if (!res.ok) throw new Error(`Episodes-by-entities error: ${res.status}`);
+    return res.json(); // { episodeIds: [...] }
+}
+
 module.exports = {
     getSessionByExternalId,
     createSession,
@@ -231,4 +241,5 @@ module.exports = {
     generateProjectSummary,
     getProjectOverviewSummary,
     searchEpisodes,
+    getEpisodesByEntities,
 }