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

Annotations already declare readOnly, idempotent, non-destructive, open-world behavior, so the safety profile is covered. The description adds real value beyond that: it discloses the shape of content_object (filename, doc_type, description, sequence, markdown availability), the citation URL pattern, and the XBRL R*.htm caveat.

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 core purpose, then supporting detail about content_object and citation. Dense but every sentence carries information; minor redundancy between the inline Args note and the schema.

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 an output schema present, return values need not be explained, yet the description still summarizes content_object fields usefully. Annotations cover safety, and the parameter example fills the 0% schema coverage gap, leaving little an agent would need to infer.

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% with one required parameter, so the description must compensate – and it does by giving the expected accession_number format with a concrete example ('0001140361-26-006577'). That is meaningful guidance beyond the bare string type in 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?

States a specific verb and resource ('Get full filing metadata') and immediately clarifies the scope by naming the key payload, content_object. It effectively differentiates itself from get_filings (list) and get_document (read one doc) by describing what content_object contains.

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 routes the agent to get_document for reading a document and to list_filing_tables for identifying XBRL table pages, which is strong when-to-use guidance. It does not explicitly contrast with get_filings or search_filings for locating a filing, leaving that inference to the agent.

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