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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds valuable behavioral context beyond that: the default returns a COMPACT DIGEST with key findings, practical application, and limitations, and section returns one sub-section. It also discloses citation behavior, which helps the agent use results correctly.

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 dense but every sentence earns its place: it states the action, the default return format, the optional parameter behavior, and when not to call. The key guidance is front-loaded in the first sentence.

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 only two simple parameters, read-only annotations, and no output schema, the description covers everything an agent needs: the refId format, the default digest contents, the section option, and the calling policy relative to search. There are no significant missing behavioral details.

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 refId and section. The description adds value by explaining the default vs. section tradeoff and providing concrete refId and section examples, making the conditional meaning of the parameters clearer than the schema alone.

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 a specific verb and resource: 'Read an entry by refId'. It clearly distinguishes itself from knowledge search by saying 'Prefer answering from the search card first; only call this when the card is insufficient.' The REF-001 / SYNTH-04 examples make the target resource concrete.

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?

Explicit when-to-use guidance is present: use the search card first, call this only when the card is insufficient. It also explains when to pass `section` for depth versus relying on the default digest. This fully routes an agent between the default and parameterized behavior.

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