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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the tool's safety profile is clear. The description adds meaningful behavioral context beyond that: unreleased records state no price, and lot-specific certificate data is intentionally excluded, directing users to a different flow. These specifics help the agent anticipate edge cases without contradicting the annotations.

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 description is two sentences: the first front-loads the primary purpose and return contents, the second addresses edge cases (unreleased records, lot-specific data). Every word earns its place; there is no fluff or repetition of the title or schema. It is compact and immediately useful.

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 two-parameter lookup tool with both parameters fully documented and no output schema, the description sufficiently covers what is returned (identity metadata, release state, availability, COA availability, evidence links), the behavior for unreleased records, and what is excluded. It provides enough context for an agent to invoke the tool correctly and interpret the result, even without an output schema.

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%: both 'slug' and 'response_format' have descriptive text in the schema. The tool description does not add parameter-level meaning beyond what the schema already provides, but it does contextualize the parameters by explaining the overall return content. Since the schema fully documents the parameters, a baseline score of 3 is appropriate; no extra semantic value is added.

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?

The description states the tool 'Returns the public record for one sequence' and lists the specific data included (identity metadata, release state, availability, COA availability, evidence links). It clearly distinguishes itself from catalog search (one vs. many) and from COA-specific tools by explicitly noting that lot-specific certificate data is not exposed, pointing to the 'signed COA flow' instead. This is a specific verb+resource with clear differentiation.

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 implies when to use the tool (to get a single sequence's public record) and gives a clear exclusion: 'Lot-specific certificate data is not exposed here; verify a specific lot through the signed COA flow.' While it does not explicitly name the sibling tool for COA lookup, it does route the agent away from this tool for lot-level verification, which is sufficient guidance for selecting among the listed siblings.

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