Semahash MCP Server

Content-addressed semantics for multi-agent coordination. Sema is a content-addressed reference system for reasoning and communication. Participants encode and hash information under an agreed representation, then reuse the content address as a verifiable reference, optionally paired with a human-readable handle. Matching full references establishes identity of the resolved hashed content; semantic equivalence…

People connecting this server to Claude, Cursor, VS Code, or another MCP client. The project is written in Python.

VERIFIED ACTIVE

LAST COMMIT 2026-08-23 · ★ 12 · #162 OF 848 MAINTAINED OTHER · VERIFIED 2026-08-25

MIT · Python servers · how we verify → /methodology

01 · Install Semahash

before you install - you'll need

GOOGLE_API_KEY

Environment variables documented in the project's README - it lists which are required and which have defaults.

Claude Code

claude mcp add emergent-wisdom-sema -- uvx semahash

Claude Desktop / Cursor / VS Code - add to config

{
  "mcpServers": {
    "emergent-wisdom-sema": {
      "command": "uvx",
      "args": [
        "semahash"
      ]
    }
  }
}

Same JSON for Cursor. For VS Code, rename the top-level key from `mcpServers` to `servers`.

Using another client? Same JSON, different key

Claude Desktop · mcpServers

Cursor · mcpServers

VS Code · servers

Windsurf · mcpServers

Zed · context_servers

Cline · mcpServers

Roo Code · mcpServers

Continue · mcpServers

LibreChat · mcpServers

Gemini CLI · mcpServers

Codex CLI · mcp_servers

Full setup guides: every client.

02 · Evidence

Security posture

What to check before giving this server access to your agent - from the registry, GitHub, and our own probes. We don't score safety; we show what's verifiable.

runs as local process (stdio) - runs on your machine with your user's permissions

license MIT - declared in the repository

pypi package semahash - check the name against the project README before installing (PyPI has no namespace ownership)

registry namespace io.github.emergent-wisdom is GitHub-verified and matches the repo owner

03 · What Semahash can do

Prose above is summarized from the project's README and registry record - no invented capabilities.

Latest releases

v0.5.3 · 2026-08-21

Added · Published versioned canonicalization-v2 golden vectors with exact preimages, · digests, normalized values, and rejection cases for independent implementations. · Fixed · Canonical hashing now rejects non-finite…

v0.5.2 · 2026-08-21

Fixed · Removed 19 stale handles from the built-in standard preset. Those handles · were absent from the current bootstrap vocabulary, so selective builds warned · and skipped them. A regression test now requires every…

v0.5.1 · 2026-08-20

Fixed · MCP now advertises the conditionally exposed write tools under their documented · public names, sema_mint and sema_pull, instead of underscore-prefixed · implementation names that clients could not call.

04 · Who maintains Semahash

semahash is maintained by emergent-wisdom. We track 2 MCP servers from emergent-wisdom - 2 actively maintained, 13 combined GitHub stars, oldest repo from Mar 2026.

05 · Facts

repository: github.com/emergent-wisdom/sema
website: https://semahash.org/
category: other - ranked #162 of 848 actively-maintained other servers as of 2026-08-25.
release cadence: 6 releases in the last 90 days (latest 2026-08-21)
registry: io.github.emergent-wisdom/semahash (active, first published 2026-04-08 · 7 versions)
packages: pypi:semahash

06 · Semahash FAQ

What is Semahash?

Is Semahash still maintained?

Yes - as of 2026-08-25, its last commit was 2026-08-23 and it shipped 6 releases in the last 90 days. We re-verify nightly.

How do I install Semahash?

Run `uvx semahash`. The README documents one environment variable (GOOGLE_API_KEY) to set first. You can also paste the ready-made client config above.

Does Semahash run locally?

Yes - it's a stdio server: it runs on your machine (via uvx) with your user's permissions. Your data stays local unless the server itself calls external APIs.

07 · Alternatives to Semahash

Alternatives to Semahash

Maintained other servers if Semahash isn't the fit.

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