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

Even with readOnlyHint/openWorldHint/idempotentHint annotations, the description adds substantial behavioral context: the USPTO source 'soft-fails until reactivated,' FDA products only cover biologics so an empty section is expected for small-molecule companies, name resolution goes through SEC EDGAR, and sources_used/sources_failed reflect real 'no data.' It also explains empty sections are not bugs and private companies return a structured resolved:false note rather than a bare error.

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 long, but the tool is genuinely complex with many output sections and source-specific caveats. It front-loads example queries and the core 'full cross-source profile' statement, then uses semicolon-separated clauses to enumerate return fields efficiently. It is dense rather than bloated, though it could be improved with bullet points or headers.

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 present, the description must fully explain return values and edge cases — and it does. It enumerates every return section (filings, fundamentals, patents, contracts, FDA products, hiring, news, LEI), states limits like 'up to 5,' explains soft-failure and empty-section behavior, and covers both success and failure modes for public versus private companies. Nothing critical 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 description coverage is 100%, so the schema already documents type and value thoroughly, including the ticker/CIK/name examples and the interchangeability of type values. The description largely restates this information (e.g., 'Pass a ticker..., zero-padded CIK..., OR a company name') without adding new per-parameter semantics. The resolved:false and name-resolution behavior is behavioral context, not parameter meaning, so the description adds no real semantic value beyond 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?

The description opens with concrete query examples and defines the tool as a 'full cross-source profile of a US public company in ONE parallel call.' It names the specific resource (public companies via SEC/XBRL/USPTO/etc.) and explicitly distinguishes itself from 'chaining single-pack SEC/XBRL/news lookups,' so an agent can easily tell it apart from siblings like compare_entities or resolve_entity.

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 gives an explicit directive: 'ALWAYS PREFER over chaining single-pack SEC/XBRL/news lookups when the user asks for a holistic view.' It also clarifies when the tool should not be expected to succeed (private companies → resolved:false) and which sources may legitimately return empty. This is strong when-to-use guidance with a clear alternative path stated.

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