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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the description adds value with the data-coverage caveat ('Covers the filings our SEC syncs collected for the company, not every filing it ever made'), the newest-first ordering, and the free-tier note. It omits pagination/row-limit behavior, which is the remaining unknown for an agent.

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 most decision-relevant token ('FREE'), then scope, then usage, then the identifier rule. Efficient overall, though the enumeration of return fields partially duplicates the parameter/return schema and costs a little length.

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?

Annotations cover safety, the schema covers all three parameters, and an output schema exists so return values needn't be restated. The description closes the remaining gaps (coverage limitation, exclusivity rule). Only pagination/limit behavior for potentially long filing timelines is unaddressed.

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 baseline would be 3. The description exceeds that by stating an exclusivity constraint the schema does not encode (zero required params, no oneOf), i.e. exactly one of companyId, symbol, or cik must be supplied. That prevents an invalid multi-identifier call.

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+resource (one company's SEC filing timeline) plus the exact scope, ordering (newest first), and the form types returned (S-1, S-1/A, F-1, EFFECT, 424B4, RW, 8-K). This is clearly distinguishable from siblings like get_ipo_events or get_ipo_overview, which cover different data.

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?

Gives concrete use cases: follow a registration from first S-1 through amendments to the final prospectus, or confirm a withdrawal (RW). It also states the identifier rule ('Provide exactly one of companyId, symbol, or cik'). It does not name a sibling tool as an alternative for closely related questions, so it falls short of a 5.

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