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

Annotations cover the safety profile (readOnly, idempotent, non-destructive, openWorld), and the description adds genuinely useful behavior beyond them: the return is Markdown plus structuredContent, and the agent must switch on result.category ('nominal' | 'verbal' | 'not_found') before reading the body. It also discloses the content source/license. It does not cover rate limits or failure/auth conditions, and part of the return-shape detail is already carried by the output schema.

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?

Front-loaded with the action, then the usage condition, then the return contract. Dense but every sentence carries distinct, load-bearing information with no filler.

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-param read tool with full schema coverage, annotations, and an output schema, the description supplies the routing condition and the category-switch consumption guidance. Nothing material an agent needs to call and consume it correctly is missing.

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 baseline is 3, but the description adds real meaning by explaining that both parameters originate from a search result's 'inflection handle', which is not stated in the schema's per-field descriptions.

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 (Fetch) and resource (full declension/conjugation table for a lemma), and specifies the exact identifier pair (entry_id + word_class from a search result's inflection handle). It distinguishes itself from the sibling search tools by scoping itself to already-identified lemmas.

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?

Explicitly states the condition for use ('only when a search ran without inline forms or left a match un-expanded') and names the alternative behavior (a default search already returns tables inline). This is a textbook when/when-not routing statement to anglo_search.

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