Inspectrum MCP server

Inspectrum

Independent review before a risky agent change becomes hard to undo.

Claude plans it. GPT reviews it. You approve it.

A plausible plan can commit an agent to a migration, authentication change, payment flow, compatibility break, or deployment that is expensive to undo.

Inspectrum is an independent pre-flight check before that decision. Its first automatic integration runs when Claude Code exits plan mode: Codex (GPT) reviews the plan before the approval dialog reaches you, findings can send the plan back for revision, and you keep final approval. If the reviewer cannot run, the plan passes through with a visible warning instead of being silently reported as reviewed.

Here, independent means a reviewer distinct from the author model, invoked separately. It does not mean their errors are statistically independent. Inspectrum makes the checkpoint repeatable and its failures visible; a net reliability gain and a defensible moat are not yet proven. The post-0.2.2 strategy defines the evidence gates and keeps code review, pull-request review, and pair programming out of scope.

When a skill is enough

For an occasional second opinion, a rule can tell one agent to call another and compare the replies. That is a reasonable lightweight option.

Inspectrum is for the repeatable checkpoint. In Claude Code, the plugin runs at the plan-to-execution boundary without relying on a remembered prompt, caps revision loops, and fails open on operational errors. Other local MCP hosts can call the same review_plan contract on demand. Both paths keep findings attributed, return a common verdict shape, preserve human control, and write local evidence for successful reviews.

Recreating those guarantees with a skill means maintaining the orchestration, output validation, health checks, failure policy, and session record yourself.

Public availability as of 1 August 2026: npm 0.2.3, the GitHub release, and the repository's Claude and Codex plugins are aligned on 0.2.3. Glama is public. The MCP Registry may still show 0.2.2; it was not republished in this pass. Inspectrum was not in the public Claude Community catalog, while PulseMCP blocked the one-time recheck with HTTP 403, so no current PulseMCP listing claim is made.

The public 0.2.3 activation evidence records exact commands, timings, one useful finding, one null result, one visible fail-open case, and the limits of the measurement.

Quick start

You need Node 20+, Claude Code, and Codex CLI >= 0.99.0 authenticated with a ChatGPT subscription (no API key):

claude plugin marketplace add yannmenec/inspectrum
claude plugin install inspectrum@inspectrum

That's the whole install. Next time you finish a plan in plan mode:

⏺ ExitPlanMode
  ⎿  inspectrum×codex: REVISE (round 1/2)          # abridged — real output
     Majors:                                       # adds a full-report path
     - [codex] Migration drops the unique index before backfilling —
       concurrent writes can insert duplicates.
       Fix: backfill first, drop the index last.
     Revise the plan to address these findings, then finish the plan again.

Shortened. The full README is on GitHub.