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

Adds meaningful behavioral detail beyond annotations: the 20,000-character cap, original length, and truncation flag. It doesn't mention auth requirements or latency, but the truncation disclosure is valuable for an agent. Annotations cover read-only and idempotency aspects.

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 sentences, each front-loading essential behavior: what it reads, the omit-section behavior, and the size/truncation contract. No wasted words.

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?

Covers the key output behavior (section text vs index, truncation) despite an output schema existing. Enough for an agent to invoke correctly, though it could mention the filing_id format or error cases.

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 0%, so the description must carry the parameter burden. It explains section omission and the default max_characters implicitly via the 20,000 cap, and names the filing_id parameter. It doesn't explain the section naming pattern or the max_characters minimum, but adds useful semantics.

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 (read) and resource (named section from an SEC filing id). Distinguishes clearly from sibling tools like filing_facts and compare_filing by scoping it to reading a single named section.

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?

Describes the omit-section behavior, which is implicit usage guidance, but doesn't state when to use this tool versus filing_facts or compare_filing. There's no explicit when/when-not guidance.

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