foreword

this is a proof of concept by claude and not suitable for production

-noah

sio-mcp

Read-only MCP server over CMU Student Information Online (SIO), built as a thin wrapper around a reusable typed client library.

Related MCP server: MCP Student Assistant

Layout

src/sio_mcp/
  utils/session.py   auth: Playwright login (AndrewID + Duo), cookie persistence
  terms.py           term codes (F26 <-> fall-2026 <-> "Fall 2026")
  models.py          pydantic models; ISO dates, 24h times, decimal-string money
  parsers/           HTML parsers for SIO's server-rendered pages
  client.py          SIOClient: typed async API with TTL caching
  server.py          the MCP server (8 read-only tools)
  cli.py             `sio-login`
tests/fixtures/      real SIO page snapshots the parser tests run against

SIOClient is the reuse surface: the MCP server, a CLI, a cron job, or a RAG ingestion script all call the same functions.

Setup

uv sync
uv run sio-login   # AndrewID + password (env: ANDREW_ID/ANDREW_PASSWORD or prompts), approve the Duo push

Sessions expire on CMU's schedule; when a tool reports an authentication error, re-run sio-login.

Register with Claude Code:

claude mcp add cmu-sio -- uv --directory /path/to/this/repo run sio-mcp

Tools

Conventions: times are America/New_York HH:MM; dates ISO YYYY-MM-DD; money is a decimal string in USD (charges positive, payments/credits negative); course codes are normalized to 15-122 form; term params accept F26, fall-2026, or Fall 2026.

Testing

uv run pytest

Parser tests run offline against tests/fixtures/. SIO redeploys weekly — if a parser starts raising UpstreamChangedError, re-capture the page into the fixtures and adjust.

Non-goals (for now)

• Writes. Registration/drop actions live in SIO's legacy GWT app behind opaque GWT-RPC, and SIO explicitly warns that automated registration requests get access revoked. This server is deliberately read-only.

• The legacy /sio/#... app generally (invoices, pay-now, planning). The data worth reading is duplicated on the server-rendered pages this uses.