HiveMind

Shared memory for AI agents, served over the Model Context Protocol. One agent contributes what it learned, another one finds it. The server speaks MCP revision 2026-07-28 (no sessions, server/discover) and the earlier handshake revisions on the same URL, through fastmcp 4.0.3.

This is a demonstration pinned to a date, not a product. It has no hosted instance, no users and no daily maintenance. The end of life section says what will break next. Everything stated here can be checked from the repository alone.

What it does

• Seven MCP tools over Streamable HTTP at /mcp: contribute, search, list, delete, publish, report an outcome, manage roles.
• Server-minted handles: add_knowledge returns a contribution_id that the client passes back as an ordinary tool argument. No protocol session is needed; the 2026-07-28 revision removed sessions and expects exactly this.
• Before storage: prompt injection scan (DeBERTa), personal data removal (Presidio with GLiNER), three-stage deduplication (MinHash, cosine, LLM), quality scoring, conflict resolution.
• Isolation by organisation and by agent, carried in the bearer token, never in tool arguments. RBAC with Casbin.
• A REST API under /api/v1, with the same organisation isolation, keyed by X-API-Key.

What it does not do

• It does not run anywhere. You run it.
• It does not ship a hosted knowledge commons; the "public" flag only shares an item between organisations of the same instance.
• The third deduplication stage and conflict resolution call an LLM and are not reachable from the MCP tools: the MinHash index they depend on is never populated by the write path. They are kept as code, documented as unwired.
• docker-compose.yml starts the server, PostgreSQL and Redis. It starts no Celery worker, so webhooks and quality signal aggregation never run in the shipped stack.
• The startup downloads the embedding model from Hugging Face on first run. A machine without network access does not start.
• The PII pass still redacts a few product names as if they were people or places: Prometheus and Grafana are the two measured cases (spaCy recognizer). Known, documented, not corrected in this release.
• A2A facade: not planned in this release.

Quick start

Requirements: Docker with Compose. Ports 8000, 5432 and 6379 free.

git clone https://github.com/AmirK-S/HiveMind.git
cd HiveMind
cp .env.example .env
docker compose up -d --build
curl -s localhost:8000/health

The first start takes a few minutes: migrations run, then three models load, one of them downloaded from Hugging Face on first run. docker compose logs -f hivemind shows the progress; the health check allows four minutes before it reports the container unhealthy.

Mint a bearer token for an organisation and an agent. There is no CLI command for it; the signing key is HIVEMIND_SECRET_KEY from your .env:

docker compose exec hivemind python -c \
  "from hivemind.server.auth import create_token; print(create_token('org-a', 'agent-1'))"

Connect an MCP client that speaks Streamable HTTP. The generic shape, to adapt to your client's configuration file:

{
  "mcpServers": {
    "hivemind": {
      "type": "http",
      "url": "http://localhost:8000/mcp",
      "headers": { "Authorization": "Bearer <token>" }
    }
  }
}

Clients that only speak stdio can go through mcp-remote with a --header argument. There is no npx launcher in this repository, and the server is not published on PyPI: it needs PostgreSQL with pgvector and Redis, so it is distributed as this repository, to build locally. The distribution name in pyproject.toml is hivemind-mcp; hivemind on PyPI is an unrelated project.

Talk to the server by hand, on the 2026-07-28 wire:

curl -s -X POST localhost:8000/mcp \
  -H 'Content-Type: application/json' -H 'Accept: application/json, text/event-stream' \
  -H 'MCP-Protocol-Version: 2026-07-28' -H 'Mcp-Method: server/discover' \
  -d '{"jsonrpc":"2.0","id":1,"method":"server/discover","params":{"_meta":{"io.modelcontextprotocol/protocolVersion":"2026-07-28","io.modelcontextprotocol/clientCapabilities":{}}}}'

Demo

scripts/demo.sh replays the whole story against a running compose stack: server/discover on the 2026-07-28 wire, two agents of one organisation, alice contributes, bob finds the item by meaning and then by handle, rates it, each agent lists only its own contributions, and a call without a token is refused. scripts/demo-transcript.txt is its output on a fresh clone on 2026-09-06.

cp .env.example .env && docker compose up -d --build && ./scripts/demo.sh

The seven tools

Tool	What it does	Refuses when
add_knowledge	Contributes a text with a category; returns contribution_id and status (queued, or auto_approved if a rule exists for the organisation)	content shorter than 10 characters, confidence outside 0.0 to 1.0, unknown category, injection detected, too much redacted, burst rate exceeded
search_knowledge	Fetches by id, or searches by query (PostgreSQL full text plus vectors, fused in SQL)	neither id nor query, unknown or foreign private item
list_knowledge	Lists the caller's own contributions, pending and approved	unknown status or category filter
delete_knowledge	Soft-deletes an item of the caller's organisation and agent	item of another agent or organisation, unknown id
publish_knowledge	Makes an item visible to other organisations, or hides it again	item of another organisation, unknown id
report_outcome	Records solved or did_not_help for an item, once per run_id	unknown item, unknown outcome
manage_roles	Reads or assigns Casbin roles and permissions	caller is not an admin of the organisation

Every refusal is an MCP error (isError: true) with a one-line message. Every tool reads Authorization: Bearer <jwt>; the JWT carries org_id and agent_id. The REST API under /api/v1 uses X-API-Key instead.

The RBAC policy table starts empty. Nobody is an admin until a policy and a role link exist in casbin_rule for the organisation; tests/test_tool_manage_roles.py shows the two rows to insert.

Protocol revision and conformance

The official suite, @modelcontextprotocol/conformance, was run before and after the upgrade from fastmcp 2.14.5 to 4.0.3. Reports, logs and the expected-failures files are in conformance/.

Requirements	Before (2.14.5)	After (4.0.3)
2025-11-25, scored scenarios passed	8 of 30	10 of 30
2026-07-28, scored scenarios passed	5 of 37	13 of 37
2026-07-28, checks passed / failed	55 / 102	111 / 56
Wire schema violations	0	0

Most of the suite drives reference tools with imposed names (test_simple_text, test_input_required_result_*) or capabilities this server does not expose (resources, prompts, completion, the tasks extension). The scenarios that judge the protocol of a tools-only server (server-stateless, tools-list, server-sse-multiple-streams, dns-rebinding-protection, caching) pass after the upgrade, except two checks of server-stateless that need a reference tool. Each remaining failure is listed with its reason in conformance/expected-failures-2026-07-28.yaml, and the tool exits 0 with it.

Almost none of the upgrade happened in this repository's code. The revision is absorbed by the framework. Two things had to change: get_http_headers() drops the Authorization header by default in fastmcp 4.x, so the eight call sites ask for it explicitly; and the DNS rebinding guard is off by default, so the server arms it with HIVEMIND_ALLOWED_HOSTS.

Tests

uv sync --extra dev
docker run -d --name hivemind-test-pg -e POSTGRES_USER=hm -e POSTGRES_PASSWORD=hm \
  -e POSTGRES_DB=postgres -p 55432:5432 pgvector/pgvector:pg16
HIVEMIND_TEST_ADMIN_URL=postgresql://hm:hm@localhost:55432/postgres uv run pytest -q -m "not models"

69 tests in that run. The three models are replaced by doubles, so none of them downloads anything or calls an LLM. One file per MCP tool, each going through POST /mcp with a bearer token against a database migrated to head, with the nominal path and at least three refusals. Without HIVEMIND_TEST_ADMIN_URL the tests that need PostgreSQL skip. CI runs the same command on every push (.github/workflows/ci.yml).

29 more tests carry the models marker: they load the real PII pipeline, so GLiNER (about 400 MB, downloaded to ~/.cache/huggingface) and the spaCy model of the models dependency group. They run separately:

uv sync --extra dev --group models
uv run pytest -q -m models

What is not tested: the REST API, the CLI, the pipelines beyond the doubles (except the PII contract), Celery tasks. The tests cover the contract of the seven tools and the protocol surface, not the rest of the code.

Configuration

All variables carry the HIVEMIND_ prefix and have a default in hivemind/config.py; .env.example lists the useful ones.

Variable	Default	Role
HIVEMIND_SECRET_KEY	dev-secret-change-me	HS256 key of the bearer tokens. Change it.
HIVEMIND_DATABASE_URL	local PostgreSQL	set by the compose file to its own service
HIVEMIND_REDIS_URL	local Redis	idem
HIVEMIND_ALLOWED_HOSTS	localhost,127.0.0.1	hostnames accepted in Host; others get 421
HIVEMIND_EMBEDDING_MODEL	sentence-transformers/all-MiniLM-L6-v2	must not change for the life of a database
HIVEMIND_ANTHROPIC_API_KEY	empty	LLM stages; empty means skipped

Repository layout

• hivemind/: the server. server/main.py builds the app (create_app()), server/tools/ holds the seven tools, pipeline/ the PII, injection and embedding stages, security/ RBAC and rate limiting, api/ the REST routes.
• alembic/: seven migrations. docker/entrypoint.sh applies them before uvicorn.
• tests/: the suite described above.
• conformance/: MCP conformance reports before and after the upgrade.
• wrappers/: hivemind-langchain and hivemind-crewai, thin clients of the REST API, also on PyPI under those names.
• scripts/: the demo, its transcript, and a script that exports the OpenAPI document of the REST API.

Removed in September 2026, still in the git history: a Next.js dashboard, two generated SDKs that had drifted from the API, a FalkorDB driver nothing imported, and a skill file with a wrong category list.

End of life

This repository serves MCP revision 2026-07-28 with fastmcp>=4.0.3,<5 and the mcp 2.1.1 SDK, pinned in uv.lock. It is not maintained on a daily basis.

What will break next: the next protocol revision will do to the session-less era what 2026-07-28 did to sessions, and the conformance suite will have to be run again with new --requirements. The tests in tests/ are the safety net for that day: they exercise the wire, not the framework's internals. The official TypeScript SDK did not speak 2026-07-28 as of 2026-09-05 (1.30.0 tops out at 2025-11-25), so editor clients will keep using the handshake era for a while; the server serves both.

Issues

Issues are welcome and are read, on a best effort basis, with no response time commitment: this is a personal demonstration repository pinned to a date, kept by one person, with no service expected of it. No feature is promised. A reproducible defect in what this README claims is the kind of issue that gets fixed; a request for a new capability gets a written answer and is closed as out of scope.

License

MIT, see LICENSE.