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

Annotations already mark this as read-only, open-world, and idempotent. The description adds substantial behavioral context beyond that: it cascades through several lookup endpoints, degrades gracefully when GLEIF/OpenFIGI are unavailable, returns figi_candidates when a name matches multiple instruments, and explicitly reports unresolved identifiers under `unresolved` rather than omitting them.

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 and heavily parenthetical, making it harder to parse quickly, but it is front-loaded with concrete examples and every section earns its place. For a tool with this many identifier systems, the length is mostly justified, though some restructuring would improve readability.

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 covers what is returned (canonical identifiers, source labels, unresolved list, figi_candidates), how enrichment degrades, what inputs are accepted, and how multi-match cases behave. An agent has enough information to invoke the tool correctly and interpret non-obvious outcomes.

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%, but the description goes well beyond the schema by explaining the type enum semantics, giving concrete example values for both company and drug, and warning that the value must be the entity name only — e.g., passing 'NEW YORK ST DORM AUTH' not 'NEW YORK ST DORM AUTH revenue bonds' because trailing security-class words break the FIGI match.

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 user-phrase examples and a crisp statement of purpose: resolving a user-spoken name to canonical/official identifiers that other tools require. It also differentiates itself from the sibling toolset by noting that it replaces 2-3 manual lookups and covers non-equity instruments that other lookups cannot reach.

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 directs the agent to 'Use FIRST whenever you have a name but need an ID,' and the supported types give clear scope. It does not name specific sibling tools to avoid or state when not to use this tool, but the guidance is still strong and actionable.

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