[BUG] False-positive AUP block on legitimate comparative-genomics annotation (Request ID included)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

A legitimate computational-biology request is blocked at the request level with an API-level Usage Policy error, before the model generates anything:

Claude Code is unable to respond to this request, which appears to violate our Usage Policy.

The task is standard comparative / evolutionary genomics: hand-annotating the exon structure of a gene-family locus in an already-published reptile genome, reproducing the gene calls from a published peer-reviewed paper as ground truth. No sequence design, no synthesis, no enhancement — purely identifying gene boundaries in existing public data. The prompt itself is a software-engineering task spec (TDD, tool reuse, repo paths) wrapped around that annotation.

The block scores subject matter, not wording: reframing the surrounding prose to foreground the research context did not clear it. It appears the classifier is triggering on toxin/venom gene-family terminology, which means published-genome annotation in toxinology/venomics is flagged as a policy violation. This matches the known false-positive class in #49751 (computational structural biology) and #61088 (workspace files), but in a distinct domain.

Request ID: req_011CbhnTs2uakyqPoTH4grT1

What Should Happen?

Gene-structure annotation of public genome data, reproducing published gene calls, should not be classified as a Usage Policy violation. This is core, openly published basic research. The classifier should distinguish annotation/analysis of existing public sequences from genuinely sensitive requests, or at minimum offer a per-request appeal path that doesn't require downgrading to a model too weak for the task.

Error Messages/Logs

Steps to Reproduce

1. Open a Claude Code session on an Opus model.
2. Submit a task prompt asking to annotate a venom/toxin gene-family locus (e.g. a PLA2 family, venom allergen family, three finger toxin family, Kunitz family etc) in a published genome, reproducing a paper's known gene calls as ground truth — i.e. a normal comparative-genomics annotation spec.
3. The request returns the API-level Usage Policy error above before any generation.
4. Rewording the prose to emphasize the legitimate research context does not clear it.
5. Switching to claude-sonnet-4-20250514 avoids the block but is too weak for the agentic multi-stage pipeline, so it is not a usable workaround.

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.162

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_