fix(mcp): launcher runs the consumer's pinned .#odu, not github:

The odu-mcp launcher defaulted to `nix run github:juspay/odu -- mcp` — an
unpinned fetch of master that (a) bypasses the npins pin the consuming repo
deliberately maintains and (b) fails outright until a release lands on master.
A consuming repo pins odu via npins and re-exports it as `.#odu`; the launcher
now runs that exact pinned output (override with ODU_FLAKE). Docs updated.

Author: srid

.apm/skills/odu-mcp/SKILL.md

@@ -12,10 +12,10 @@ that re-exposes a live CI run as agent tools (`run`, `get_nodes`, `tail_log`,
 `odu://log/{node}`), so Claude Code / Codex / opencode / Gemini CLI drive CI
 with structured calls instead of scraping terminal output.
 
-`bin/serve` is self-contained — it resolves odu via `nix run` and serves over
-stdio in the consumer's repo (dialing `.ci/odu.sock`). Set `ODU_FLAKE` to
-override the odu flake-ref (default `github:juspay/odu`); a repo that
-re-exports odu can point it at its own pinned output with `ODU_FLAKE=.#odu`.
+`bin/serve` resolves odu through the consuming repo's own pinned flake output
+(`nix run .#odu -- mcp`) and serves over stdio in that repo (dialing
+`.ci/odu.sock`) — the exact, npins-pinned odu the repo's CI uses, never an
+unpinned `github:` fetch. Override the flake-ref with `ODU_FLAKE`.
 
 Full docs in the [repo README](https://github.com/juspay/odu/blob/master/README.md).
 

.apm/skills/odu-mcp/bin/serve

@@ -1,13 +1,12 @@
 #!/usr/bin/env bash
-# Launch the odu MCP server — odu's agent face. Resolves odu via Nix and runs
-# `odu mcp` in the current directory: the server dials `.ci/odu.sock` and
-# starts / attaches to runs in the cwd, so an MCP host launching this from the
-# repo root drives that repo's CI. Self-contained — no surrounding devshell
-# required. Requires flakes (`experimental-features = nix-command flakes`).
+# Launch the odu MCP server — odu's agent face. Runs `odu mcp` in the current
+# directory: the server dials `.ci/odu.sock` and starts / attaches to runs in
+# the cwd, so an MCP host launching this from the repo root drives that repo's
+# CI. Requires flakes (`experimental-features = nix-command flakes`).
 #
-# Override knobs (env vars):
-#   ODU_FLAKE   — flake-ref for odu (default: github:juspay/odu). A consuming
-#                 repo that re-exports odu can point this at its pinned output,
-#                 e.g. ODU_FLAKE=.#odu
+# Resolves odu through the CONSUMING repo's own flake output (`.#odu`) — the
+# repo pins odu via npins and re-exports it, so the agent face is the exact,
+# pinned odu the repo's CI uses (never an unpinned `github:` fetch). Override
+# with ODU_FLAKE for a non-standard output or an out-of-tree odu.
 set -euo pipefail
-exec nix run --accept-flake-config "${ODU_FLAKE:-github:juspay/odu}" -- mcp "$@"
+exec nix run --accept-flake-config "${ODU_FLAKE:-.#odu}" -- mcp "$@"

README.md

@@ -162,14 +162,16 @@ The agent loop is `run` → `wait_for_settle` (fail-fast) → read the red node'
 { "mcpServers": { "odu": {
   "type": "stdio",
   "command": "nix",
-  "args": ["run", "github:juspay/odu", "--", "mcp"] } } }
+  "args": ["run", ".#odu", "--", "mcp"] } } }
 ```
 
-Repos that manage agent config with [APM](https://github.com/juspay/apm) get
-this wired automatically by depending on `juspay/odu`: odu's `apm.yml` declares
-the MCP server, deploying the `odu-mcp` launcher and the `.mcp.json` entry into
-the consumer's tree (set `ODU_FLAKE=.#odu` to use a repo's own pinned odu
-instead of `github:juspay/odu`).
+`.#odu` is the repo's own pinned odu (it pins odu via npins and re-exports it),
+so the agent face is the exact odu the repo's CI uses — never an unpinned
+`github:` fetch. Repos that manage agent config with
+[APM](https://github.com/juspay/apm) get this wired automatically by depending
+on `juspay/odu`: odu's `apm.yml` declares the MCP server, deploying the
+`odu-mcp` launcher and the `.mcp.json` entry into the consumer's tree (the
+launcher runs `.#odu`; override with `ODU_FLAKE`).
 
 ## Honest notes