wg21-wiki-mcp

A local Model Context Protocol (stdio) server that gives an LLM agent read access to the WG21 (ISO C++) committee wiki at wiki.isocpp.org as a verifiable source of truth.

The committee wiki requires a login even to read, and its agendas, straw polls, documents, and subgroup pages are otherwise hard to reach from an agent. This server authenticates with your credentials, fetches pages live over the MediaWiki API, and caches them - returning the exact wiki text with a clickable URL and revision id so every answer can be verified.

Access requires WG21 membership. This tool stores nothing confidential in its source and never logs page content. See SECURITY.md.

What it does

• Verifiable content. Tools return wikitext byte-for-byte with provenance (canonical URL, permanent oldid URL, revid, last-edit time). Nothing is summarized or reformatted by the server.

• Authentication, no browser. Prefers a MediaWiki bot password; falls back to your normal account via headless SSO (SimpleSAMLphp) if no bot password is set. The working path is pinned and reused; sessions that drop are transparently re-established.

• Shared, meeting-aware cache. A cross-process SQLite cache in ~/.isocpp.wiki/ is shared by all your local agents. Pages are cached for a week normally and re-checked hourly during the three-times-a-year meetings (detected from the public meetings calendar).

• Token-lean tools with opaque-cursor pagination and UTF-8-safe chunking of long pages.

Related MCP server: Grounded Code MCP

Install

Install from PyPI (recommended):

pipx install wg21-wiki-mcp
# or, into a venv:
pip install wg21-wiki-mcp

Pin a version for reproducibility, e.g. pip install wg21-wiki-mcp==0.2.0.

Or run without a manual install via uv:

uvx wg21-wiki-mcp
# pinned release:
uvx --from wg21-wiki-mcp==0.2.0 wg21-wiki-mcp

Install from GitHub when you need a specific commit or branch:

pipx install "git+https://github.com/cppalliance/wg21-wiki-mcp.git@v0.2.0"
# or track the latest release branch:
uvx --refresh --from git+https://github.com/cppalliance/wg21-wiki-mcp.git@master wg21-wiki-mcp

Or from a local clone (for development):

git clone https://github.com/cppalliance/wg21-wiki-mcp
cd wg21-wiki-mcp
pip install -e ".[dev]"

Requires Python 3.10+. Works on Windows, macOS, and Linux.

Configure

The wiki base URL is fixed (https://wiki.isocpp.org), so only credentials are needed. With an MCP host, pass them in the server's launch env block. The simplest setup uses the PyPI package via uvx:

{
  "mcpServers": {
    "wg21-wiki": {
      "command": "uvx",
      "args": [
        "--from",
        "wg21-wiki-mcp==0.2.0",
        "wg21-wiki-mcp"
      ],
      "env": {
        "WIKI_BOT_USERNAME": "YourAccount@yourbot",
        "WIKI_BOT_PASSWORD": "the-bot-password"
      }
    }
  }
}

To always run the newest PyPI release instead of a pinned version, use "wg21-wiki-mcp" (no version pin) as the --from value. Pinning a version is recommended for a source-of-truth tool so behavior is reproducible. To install from Git instead, use "git+https://github.com/cppalliance/wg21-wiki-mcp.git@v0.2.0".

If you installed the console script (via pipx/pip), use "command": "wg21-wiki-mcp" with no args instead. To use your normal account instead of a bot password, supply WIKI_USER_USERNAME / WIKI_USER_PASSWORD (requires that MFA is not enabled). If both are present, the bot password is used by default. See .env.example for optional tuning (cache directory, TTLs, meeting overrides). A bot password is created at Special:BotPasswords with the Read grant and is the recommended, revocable option.

Tools

Quickstart (programmatic)

from wg21_wiki_mcp.config import Config
from wg21_wiki_mcp.context import ServerContext
from wg21_wiki_mcp import tools

ctx = ServerContext.create(Config.from_env())

# Search, then read a page verbatim with a verifiable URL.
hits = tools.search_wiki(ctx, "some topic", limit=5)
page = tools.get_page(ctx, hits.hits[0].title)
print(page.provenance.url, page.provenance.revid)
print(page.content)  # exact wikitext

Dependencies

• mcp - the MCP/FastMCP server framework.

• requests + mwclient - MediaWiki API access (re-login, batched fetch).

• beautifulsoup4 + lxml - parse the SSO login form for headless user auth.

• pydantic - structured tool outputs.

• python-dotenv - optional .env loading for local dev.

• filelock - cross-process single-flight page locking.

Error contract

Every tool error surfaces as a structured McpError with a distinct, documented code. Messages are actionable and contain no credentials or wiki page content.

See ARCHITECTURE.md for the full invariants.

Versioning and stability

The package is 0.x Alpha (Development Status :: 3 - Alpha). Until 1.0.0:

• Pin a version in your MCP config (@v0.2.0 or a PyPI release) so upgrades are deliberate.

• Stable: MCP tool names, tool parameter names/types, application error codes (1–4, -32602), and all Provenance fields plus PageContent.content / section (any other required provenance field is stable too — see STABILITY.md). Breaking changes to these require deprecation for at least one minor version first.

• Unstable: response-model optional fields, pagination cursor format, on-disk cache layout, internal Python modules, and log message wording may change in any 0.x release without prior deprecation.

• 0.x minor bumps (0.2.0 → 0.3.0) may add tools or deprecate stable APIs; unstable-tier breaking changes can land without a deprecation period.

• 0.x patch bumps are bug fixes and non-contract changes.

Read STABILITY.md for the full tier list, deprecation process, and post-1.0 plans. Check CHANGELOG.md (including ### Deprecated) before upgrading a pinned version.

Documentation

• docs/API.md - MCP tool reference (generated from source; run python scripts/build_api_docs.py to update).

• STABILITY.md - API stability tiers and deprecation policy (pre-1.0).

• docs/RUNBOOK.md - MCP host setup, troubleshooting, and agent tool-selection guide.

• docs/FIRST_PYPI_PUBLISH.md - one-time Trusted Publisher setup for the first PyPI release.

• ARCHITECTURE.md - design, data flow, parse-vs-offload policy, what may break, future work.

• CONTRIBUTING.md - dev setup, tests, confidentiality rules, governance, and where to start reading.

• SECURITY.md - credential handling and confidentiality.

License

Boost Software License 1.0 - see LICENSE.