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

The description goes far beyond the annotations by disclosing detailed behaviors: graceful degradation if GLEIF/OpenFIGI is unavailable, assertion of nothing and return of figi_candidates when ambiguous, explicit listing of unresolved identifiers under 'unresolved', and internal cascading through lookups. These are valuable behavioral traits not inferable from readOnlyHint or idempotentHint.

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 information-dense; each sentence adds locally relevant context for a complex entity-resolving tool. It is front-loaded with examples and high-level purpose, then details. While some redundancy exists (e.g., repeated mentions of FIGI), overall it earns its length given the tool's complexity, but it could be tightened slightly without losing value.

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?

The description fully covers what an agent needs to know to call the tool correctly: input formats, supported types, behavioral on ambiguity, graceful degradation, and how different identifiers are sourced. Since there is no output schema, the description adequately explains return-like concepts (figi_candidates, unresolved), and annotations already cover safety. 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 coverage is 100%, but the description adds substantial meaning beyond the schema. For the 'value' parameter, it provides crucial guidance about passing only the entity name and warns against including security-class words like 'revenue bonds' with a concrete example. It also explains how ISIN input resolves via the GLEIF mapping, enriching the semantics beyond the schema's brief text.

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 that the tool resolves a user-spoken name to canonical/official identifiers, which is a specific verb and resource. It enumerates the supported types (company, drug) and explicitly mentions cross-source identifiers (CIK, ticker, LEI, FIGI, RxCUI), distinguishing it from siblings. It also notes the specific use case of resolving names to IDs that other tools require.

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 'Use FIRST whenever you have a name but need an ID', which is clear when-to-use guidance. It also explains that it replaces multiple manual lookups. However, it does not explicitly mention when not to use it or name alternative sibling tools (like entity_profile) for other purposes, so it lacks full when-not/alternatives coverage.

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