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

Annotations already declare readOnly, idempotent and non-destructive, so safety is covered. The description adds non-obvious traits: the missing by-id endpoint constraint and that .pdf-suffix/fiscal-year gotchas are handled internally, which an agent could not learn from annotations alone.

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 tight sentences, front-loaded with the action and resource, then the constraint rationale, then the return shape. No filler or repetition of schema fields.

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 no output schema, the description compensates by naming the returned fields (company, title, category, timestamp, document URL). Combined with 100% param coverage and annotation-declared safety, an agent has everything needed to call it correctly.

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 coverage is 100%, so the schema already documents both parameters. The description adds real value beyond the schema by explaining why both are unavoidable (no by-id-only endpoint) and noting that id should be the bare value without .pdf/.zip suffix.

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 (a single 1INFO disclosure), and explicitly ties it to oneinfo_search_disclosures as the source. An agent can distinguish this retrieval tool from its search sibling without opening either schema.

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 clearly frames usage: it operates on results 'returned by oneinfo_search_disclosures' and explains that both id and date are required because the source only exposes by-day listings. It stops short of an explicit when-not or exclusion, but the sequencing context is strong.

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