Feat threads

[aka-sacci-ccr]

Summary by cubic

Adds thread storage and tools for saving/retrieving conversation history, plus a generate-with-thread tool that merges context and auto-saves user/assistant messages. This enables persistent, per-thread LLM chats backed by Postgres.

• New Features

  • PostgreSQL schema for threads and messages with indexes; created on config change.
  • SAVE_THREAD_DATA and RETRIEVE_THREAD_DATA tools; saves messages in user→assistant pairs and returns ordered pairs.
  • LLM_DO_GENERATE_WITH_THREAD: loads thread history, calls LLM_DO_GENERATE, persists the turn, and commits wallet usage.
  • Runtime wiring: registers thread tools, adds DATABASE binding to state, and scopes.
  • runSQL helper using DATABASE::DATABASES_RUN_SQL with basic param sanitization.

• Migration

  • Configure the DATABASE binding (@deco/postgres) in Env.
  • Grant scope DATABASE::DATABASES_RUN_SQL.
  • Deploy or reload configuration to auto-create the threads tables.

^{Written for commit 40544ec. Summary will update on new commits.}

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[cubic-dev-ai]

4 issues found across 6 files

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="deco-llm/server/db/postgres.ts">

<violation number="1" location="deco-llm/server/db/postgres.ts:28">
P1: Missing optional chaining on `DATABASE`. If `state` exists but `DATABASE` is undefined, accessing `.DATABASES_RUN_SQL()` will throw.</violation>
</file>

<file name="deco-llm/server/tools/threads.ts">

<violation number="1" location="deco-llm/server/tools/threads.ts:247">
P2: JSON.parse without try-catch can throw on malformed data. If stored JSON is corrupted, this will crash the request. Consider wrapping in try-catch with fallback to null or logging the error.</violation>

<violation number="2" location="deco-llm/server/tools/threads.ts:268">
P2: JSON.parse without try-catch can throw on malformed thread metadata. Consider adding error handling.</violation>
</file>

<file name="deco-llm/server/tools/llm-with-thread.ts">

<violation number="1" location="deco-llm/server/tools/llm-with-thread.ts:148">
P1: Falsy check on `cost` will incorrectly throw an error when cost is 0 (a valid value for cached/free responses). Use explicit `undefined` or `null` checks instead.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P1: Missing optional chaining on DATABASE. If state exists but DATABASE is undefined, accessing .DATABASES_RUN_SQL() will throw.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At deco-llm/server/db/postgres.ts, line 28:

<comment>Missing optional chaining on `DATABASE`. If `state` exists but `DATABASE` is undefined, accessing `.DATABASES_RUN_SQL()` will throw.</comment>

<file context>
@@ -0,0 +1,33 @@
+    return p;
+  });
+  const response =
+    await env.MESH_REQUEST_CONTEXT?.state?.DATABASE.DATABASES_RUN_SQL({
+      sql,
+      params: sanitizedParams,
</file context>

Suggested change

	await env.MESH_REQUEST_CONTEXT?.state?.DATABASE.DATABASES_RUN_SQL({
	await env.MESH_REQUEST_CONTEXT?.state?.DATABASE?.DATABASES_RUN_SQL({

[cubic-dev-ai]

P1: Falsy check on cost will incorrectly throw an error when cost is 0 (a valid value for cached/free responses). Use explicit undefined or null checks instead.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At deco-llm/server/tools/llm-with-thread.ts, line 148:

<comment>Falsy check on `cost` will incorrectly throw an error when cost is 0 (a valid value for cached/free responses). Use explicit `undefined` or `null` checks instead.</comment>

<file context>
@@ -0,0 +1,276 @@
+        threadMessages = threadData.messages;
+      } catch (error) {
+        // Thread doesn't exist - continue with empty array
+        if (
+          error instanceof Error &&
+          error.message.includes("not found")
</file context>

Suggested change

	if (
	error instanceof Error &&
	error.message.includes("not found")
	if (
	usageReport?.providerMetadata?.openrouter?.usage?.cost === undefined ||
	usageReport?.providerMetadata?.openrouter?.usage?.cost === null
	) {

[cubic-dev-ai]

P2: JSON.parse without try-catch can throw on malformed thread metadata. Consider adding error handling.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At deco-llm/server/tools/threads.ts, line 268:

<comment>JSON.parse without try-catch can throw on malformed thread metadata. Consider adding error handling.</comment>

<file context>
@@ -0,0 +1,283 @@
+
+      // Parse thread metadata
+      const threadMetadata = thread.metadata
+        ? (JSON.parse(thread.metadata) as Record<string, unknown>)
+        : null;
+
</file context>

[cubic-dev-ai]

P2: JSON.parse without try-catch can throw on malformed data. If stored JSON is corrupted, this will crash the request. Consider wrapping in try-catch with fallback to null or logging the error.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At deco-llm/server/tools/threads.ts, line 247:

<comment>JSON.parse without try-catch can throw on malformed data. If stored JSON is corrupted, this will crash the request. Consider wrapping in try-catch with fallback to null or logging the error.</comment>

<file context>
@@ -0,0 +1,283 @@
+        role: row.role,
+        content: row.content,
+        created_at: row.created_at,
+        metadata: row.metadata ? (JSON.parse(row.metadata) as Record<string, unknown>) : null,
+        tool_calls: row.tool_calls ? (JSON.parse(row.tool_calls) as unknown[]) : null,
+        tokens_used: row.tokens_used,
</file context>