agents-memory-sidecar

v0.6.0

Published

a month ago

Local-first shared memory sidecar for MCP-capable AI agents.

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davidfront

mcp agents memory sidecar postgresql

Agents Memory Sidecar

Local-first shared memory for MCP-capable AI agents.

Breaking change in 0.4.0: token registry files now store SHA-256 hex digests of bearer tokens as keys — plaintext tokens are rejected at startup. Convert an existing file with node scripts/migrate-http-tokens.mjs --file <path>, or generate fresh tokens with scripts/upsert-http-token.mjs. See the CHANGELOG for details.

Agents Memory Sidecar lets tools such as Codex, Claude Code, Grok, agy, Pi, and other MCP clients share operational memory through one local sidecar. It is designed for coding agents that need to search prior context before changing a project and store durable non-secret facts after work is validated.

Agent CLI -> stdio MCP wrapper -> localhost HTTP sidecar -> PostgreSQL + pgvector

The HTTP server is intended to listen on 127.0.0.1 only. Do not expose it directly to the public internet.

Features

MCP tools for searching, reading, and writing shared memory
Project context storage for stable paths, services, ports, and conventions
Short-lived agent observations with TTL
HTTP sidecar with bearer-token authentication
Actor identity derived from token registry, not model-provided fields
PostgreSQL persistence with pgvector-backed semantic and hybrid search
Secret rejection for common token/private-key patterns
Audit events for writes, permission denials, unauthorized calls, and pruning
Fake JSON store for local development and smoke tests

MCP Tools

memory_search
memory_get
project_context_get
memory_add
agent_observation_add
project_context_set (admin-only)

Search Modes

Search defaults to keyword/full-text mode. PostgreSQL deployments can enable semantic or hybrid mode after backfilling memory_embeddings; see Configuration and Semantic And Hybrid Search.

Guides

Quick Start

Install From Source

git clone https://github.com/zenbordercom/agents-memory-sidecar.git
cd agents-memory-sidecar
npm install
npm run build

Validate the checkout and build output:

node scripts/check-installation.mjs --profile quickstart --pretty

Demo Mode

Demo mode uses the fake JSON store and does not require PostgreSQL, systemd, or production config files:

npm run smoke
npm run http:smoke
npm run http:bridge-smoke

Use the fallback CLI against the fake store:

AGENT_MEMORY_AGENT_ID=local-cli \
AGENT_MEMORY_RUNTIME=local \
AGENT_MEMORY_ROLE=writer \
AGENT_MEMORY_PROJECTS='*' \
node dist/cli.js memory_add '{
  "tenant":"default",
  "project":"demo-app",
  "namespace":"ops",
  "kind":"note",
  "title":"Demo memory",
  "body":"Agents Memory Sidecar demo mode is running with the fake store.",
  "source_type":"manual"
}'

Search it:

AGENT_MEMORY_AGENT_ID=local-cli \
AGENT_MEMORY_RUNTIME=local \
AGENT_MEMORY_ROLE=writer \
AGENT_MEMORY_PROJECTS='*' \
node dist/cli.js memory_search '{
  "tenant":"default",
  "project":"demo-app",
  "query":"demo mode",
  "limit":5
}'

Local HTTP Sidecar Mode

HTTP authentication fails closed. agents-memory-http will not listen unless a valid token registry is configured (AGENT_MEMORY_HTTP_TOKENS_FILE or AGENT_MEMORY_HTTP_TOKENS_JSON). For deliberate loopback demos only, set AGENT_MEMORY_ALLOW_UNAUTHENTICATED_LOCAL=1 with a loopback bind host. GET /healthz stays unauthenticated for local liveness checks.

Create a private local token registry. Generate the bearer token yourself and pass it to the upsert helper — the registry stores only its SHA-256 digest:

mkdir -p .local/agents-memory
export AGENT_MEMORY_HTTP_BEARER_TOKEN="$(node -e "console.log(require('node:crypto').randomBytes(32).toString('base64url'))")"
node scripts/upsert-http-token.mjs \
  --file .local/agents-memory/http-tokens.json \
  --token "$AGENT_MEMORY_HTTP_BEARER_TOKEN" \
  --agent-id local-cli \
  --runtime local \
  --role writer \
  --projects '*'

The upsert script prints a fingerprint only and never echoes the token. Keep AGENT_MEMORY_HTTP_BEARER_TOKEN exported in whichever shell calls the CLI below.

Start the HTTP sidecar in one terminal:

AGENT_MEMORY_HTTP_TOKENS_FILE="$PWD/.local/agents-memory/http-tokens.json" \
AGENT_MEMORY_HTTP_HOST=127.0.0.1 \
AGENT_MEMORY_HTTP_PORT=18790 \
npm run http:dev

In another terminal, call it through the CLI HTTP backend (re-export AGENT_MEMORY_HTTP_BEARER_TOKEN with the value you generated above if you opened a new shell):


AGENT_MEMORY_BACKEND=http \
AGENT_MEMORY_HTTP_BASE_URL=http://127.0.0.1:18790 \
AGENT_MEMORY_AGENT_ID=local-cli \
AGENT_MEMORY_RUNTIME=local \
AGENT_MEMORY_ROLE=writer \
AGENT_MEMORY_PROJECTS='*' \
node dist/cli.js memory_add '{
  "tenant":"default",
  "project":"demo-app",
  "namespace":"ops",
  "kind":"note",
  "title":"HTTP sidecar demo",
  "body":"The local HTTP sidecar accepts bearer-token memory writes.",
  "source_type":"manual"
}'

Search it:

AGENT_MEMORY_BACKEND=http \
AGENT_MEMORY_HTTP_BASE_URL=http://127.0.0.1:18790 \
AGENT_MEMORY_AGENT_ID=local-cli \
AGENT_MEMORY_RUNTIME=local \
AGENT_MEMORY_ROLE=writer \
AGENT_MEMORY_PROJECTS='*' \
node dist/cli.js memory_search '{
  "tenant":"default",
  "project":"demo-app",
  "query":"HTTP sidecar",
  "limit":5
}'

Durable PostgreSQL Mode

Use PostgreSQL when you want durable shared memory:

AGENT_MEMORY_BACKEND=postgres \
PGDATABASE=agent_memory \
npm run db:migrate

Then run the PostgreSQL smoke test:

npm run postgres:smoke

See PostgreSQL Quickstart for a complete local database setup.

Installation Options

Install the current npm release:

npm install -g [email protected]

Verify the registry version and dist-tag:

npm view agents-memory-sidecar version
npm view agents-memory-sidecar dist-tags.latest

Both commands should print 0.3.1.

You can also install the matching GitHub release tag:

npm install -g github:zenbordercom/agents-memory-sidecar#v0.3.1

Or install the GitHub release tarball:

npm install -g https://github.com/zenbordercom/agents-memory-sidecar/releases/download/v0.3.1/agents-memory-sidecar-0.3.1.tgz

The CLI entry points are:

agents-memory --help
agents-memory-mcp
agents-memory-http

agents-memory: JSON CLI for direct commands and fallback automation.
agents-memory-mcp: stdio MCP wrapper for agent clients.
agents-memory-http: local HTTP sidecar.

Quick Start Troubleshooting

Missing dist/*.js: run npm run build.
Missing token registry / startup refused: create a registry with scripts/upsert-http-token.mjs, set AGENT_MEMORY_HTTP_TOKENS_FILE, and restart. Tokenless mode requires AGENT_MEMORY_ALLOW_UNAUTHENTICATED_LOCAL=1 on loopback only.
HTTP connection refused: start agents-memory-http or npm run http:dev, then run node scripts/check-installation.mjs --profile quickstart --check-http --expected-backend fake --pretty.
unauthorized: send Authorization: Bearer <token> from the registry.
permission_denied: check that the bearer token actor has the required role and project access.

Agent Setup

The recommended client pattern is:

Store the bearer token in a private env file.
Create a small launcher script that sources that env file.
Point the agent's MCP config at the launcher.

See Agent Integrations and integrations/*/README.md.

Security Defaults

Bind the HTTP sidecar to 127.0.0.1.
Require a token registry; do not rely on fail-open environment actor fallback.
Keep full bearer tokens out of Git, chat, logs, and docs.
Use separate tokens per agent.
Give normal agents writer, not admin.
Store stable facts, not secrets or raw .env files.
Treat model-provided actor fields as untrusted.

See Security Model.

Production Operations

Optional scripts and systemd unit examples are included for local Linux deployments. Review paths, users, groups, database roles, and backup passphrase handling before use.

sudo scripts/install-local.sh

See Operations and Backup And Restore.

Limitations

Search defaults to keyword/full-text mode. Semantic and hybrid search require stored embeddings and an embedding model or explicit query embedding.
The project does not replace an agent's internal conversation memory.
The sidecar is local-first and not designed as a public multi-tenant SaaS API.
Fresh install automation is intentionally minimal in this version.

What This Is Not

Not a hosted SaaS API or public internet service.
Not an agent scheduler or orchestration framework.
Not a secret manager.
Not full conversation memory.
Not a replacement for each agent's native session state.

License

Apache-2.0.