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

With readOnlyHint, idempotentHint, and destructiveHint already present, the description still adds substantial behavioral context: coverage may be truncated by history window with _warnings, out-of-plan responses return 403 PLAN_TIER_INSUFFICIENT_COVERAGE, coverage keys differ by jurisdiction, and the response is identity/coverage only. There is no contradiction with annotations.

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 every section earns its place: entry-point guidance, exact parameter examples, jurisdiction-specific coverage semantics, warning behavior, and downstream routing. It is front-loaded with the core verb/resource and organized so the most critical usage guidance appears first.

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?

Despite having no output schema, the description explains what the response contains (jurisdiction, registrant id, filings-list URL, coverage map, normalized_form), what can go wrong (truncation, 403), and what to do next. For a multi-jurisdiction lookup tool with this complexity, 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 description coverage is 100%, so the schema already documents all parameters, including jurisdiction-specific examples and the 'exactly one of' rule. The description largely repeats that information rather than adding meaning beyond the schema. Baseline 3 is appropriate.

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 a specific verb and resource: 'Resolve one company and return its identity plus a coverage summary'. It clearly positions this as the entry point for discovering filings before calling downstream tools like get_filing_facts, thereby distinguishing it from the many data-retrieval siblings.

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?

Usage context is explicit: use this when you only know a company identifier and need to discover what filings exist before calling downstream tools. It also states what the tool does NOT return and recommends follow-up tools. However, it does not explicitly describe when-not-to-use alternatives such as list_companies or search_stocks, so it falls just 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.