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

Going well beyond the readOnly/openWorld/idempotent annotations, the description discloses that it fans out across many sources, reports sources_used/sources_failed, treats empty sections as genuine 'no data', and returns resolved:false with a notes line for private companies rather than a bare failure. This gives agents accurate expectations about behavior and failure modes.

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 dense but every clause earns its place; it packs examples, input formats, source list, return fields, and failure behavior into a compact block. The long semicolon-heavy sentences are slightly harder to parse, but the content is well front-loaded with user-intent examples.

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 no output schema, the description compensates fully by enumerating return fields (cik, company_name, recent_filings, fundamentals, sources_used/sources_failed, resolved_from/to) and failure behavior for private companies. It gives an agent enough detail to invoke the tool and interpret the response correctly.

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 schema already documents both parameters well. The description adds meaningful behavioral nuance beyond the schema, such as resolved_from/resolved_to when a name is passed, name resolution via SEC EDGAR, and the note that type accepts 'company' or 'ticker' interchangeably.

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 produces a full cross-source profile of a US public company in one parallel call, with verbs like 'tell me about', 'research', and 'brief me on'. It distinguishes itself from chaining individual SEC/XBRL/news lookups, making its scope and resource 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?

The description explicitly says to ALWAYS PREFER this tool over chaining single-pack lookups when a holistic view is requested. It also specifies acceptable input forms, private-company behavior, and the meaning of empty sections, giving clear conditions for appropriate use.

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