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

Annotations already cover readOnly/openWorld/non-destructive, but the description adds real behavioral detail beyond them: identifiers.org pattern matching per namespace scanned over the text, one batched search per archive, and the important false-positive policy — a span is listed only when the archive resolves it, otherwise reported as unresolved. That is substantive, non-obvious semantics. It stops short of describing pagination/limits or result ordering.

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?

Three sentences, front-loaded with the core action and ending on the actionable handoff to fetch_record. Dense but every sentence contributes; the nested clause about pattern scanning is slightly heavy but informative.

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?

With an output schema present, return values need not be explained, and annotations cover the safety profile. The description supplies the resolution policy and downstream step, which are the pieces an agent most needs. Minor gap: it doesn't clarify how _files/_subject interact with the text scan for this particular call.

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 itself documents text, _files, and _subject. The description reinforces that `text` is the scanned input but adds no syntax or format guidance for _files/_subject beyond what the schema already carries. Baseline 3 applies.

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 and resource ('Find the sequence accessions a text names') and scopes the input explicitly (a paper's methods, a notebook, a report). It also distinguishes itself from fetch_record by designating this tool as the accession-discovery step whose output feeds the fetch. An agent can tell what it does and where it sits in the pipeline.

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?

Gives a clear usage context (scanning prose-like text for identifiers) and an explicit downstream handoff ('Hand `accessions` to fetch_record'). It does not state exclusions or name a competing tool for the same job, but the workflow routing is unambiguous.

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