Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond the destructiveHint/idempotentHint annotations, it discloses genuinely valuable behavior: the library item is preserved, entries are shared across every document bound to the plan (boundDocuments from traceable_test_plan_read) and survive archiving/deletion of this document, and the affected Test Plan row is pushed into a review state.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The core action is front-loaded in the first sentence, followed by a clarification of non-deletion and then ownership/persistence semantics. Every sentence carries information, though the persistence paragraph is somewhat long for the value it adds.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 5-parameter mutation tool with nested objects and no output schema, the description covers side effects, scope, and persistence well. Minor gaps remain: it doesn't state permission/auth requirements or whether the uploaded file itself (versus the library item) is retained.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents row/entry/reference/step. The description adds limited extra meaning ('by REF code or item id, whichever document attached it'), which closely mirrors the schema's own description of the reference parameter. Baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource (remove file evidence from a Test Plan entry or step) and immediately bounds the scope by clarifying that the Reference Library item itself is not deleted. This clearly separates it from the sibling evidence_add and evidence_upload tools.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description establishes clear context for when to use it: to detach a file reference while explicitly preserving the underlying Reference Library item, implying a different tool is needed for true deletion. It does not, however, explicitly name an alternative tool or state hard exclusions, so it stops short of the 5 bar.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.