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

Annotations already indicate read-only and idempotent behavior; the description adds that it returns an error if no summary exists, typical response size, and use of page citations. This provides useful context beyond 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 concise, front-loads the main purpose, and uses formatting (bold, bullet points) to improve readability. A few sentences efficiently convey necessary information.

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?

Given no output schema, the description outlines the return structure (sections, error envelope) and provides enough detail for an agent to understand what the tool provides. It covers key behaviors like error handling and citation format.

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% with a good parameter description; the description adds validation details (regex pattern) and error handling for invalid values, which enriches the schema.

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 clearly states the tool returns an actuarial narrative summary for a single SERFF id, listing specific sections like Filing Type and 'What This Filing Does'. It distinguishes from siblings by calling it the 'fastest route' and noting the response size, making the purpose unambiguous.

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?

It specifies when to use (when you have a SERFF id and want to understand changes) and provides fallback tools (list_filing_source_files, mcp_health) for missing summaries, advising not to retry. However, it does not explicitly contrast with other sibling tools like get_filing_extracts.

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