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

Annotations already cover the safety profile (readOnlyHint, openWorldHint, destructiveHint=false), yet the description adds substantial non-obvious behavior: coverage starts 2016, period_of_report is systematically empty for most form types and unreliable for sorting, v1A is metadata-only with the proxy body unextracted, and primary_document_url is the escape hatch to the source HTML. This is exactly the extra context annotations cannot supply.

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 purpose, then usage triggers, then coverage caveats — a sensible order and every block is actionable. It is long, however, and the bulleted filing-type glossary partially restates enum values already present in the schema, so it is thorough rather than maximally tight.

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?

No output schema exists, so the description carries the return-value burden itself and does: it lists the returned metadata fields (ticker, company name, CIK, filing type, dates, primary document URL) and states plainly that the proxy body is not extracted. For a 10-parameter tool with zero required params and no output schema, nothing essential 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 coverage is 100% (baseline 3), but the description goes well beyond it: it defines each DEF 14A family member, explains the convenience flags, warns that sort_by='period_of_report' is unreliable and filing_date should be preferred, and tells the agent that ticker is primary-class-only while company_cik retrieves every share class. These are semantics the enum values alone do not convey.

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?

Opens with a precise verb+resource ('Returns Schedule 14A proxy filings') and immediately defines what a proxy filing is, so the agent can distinguish it from the many sibling SEC-filing tools (insider, NPORT, tender offers, comment letters). The scope — public-company shareholder meeting documents — is 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?

Explicitly enumerates trigger scenarios (executive compensation, board elections, shareholder proposals, M&A votes, proxy contests, auditor changes, say-on-pay, annual meetings) and gives selection guidance for alternatives within the tool (use filing_type='DEFM14A' for M&A only; query by company_cik instead of ticker for dual-class issuers).

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