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

Even with readOnlyHint, openWorldHint, idempotentHint, and destructiveHint annotations, the description adds substantial behavioral detail: graceful degradation when GLEIF/OpenFIGI are unavailable, ambiguous matches returning figi_candidates rather than asserting, unresolved identifiers listed explicitly, ISIN-to-LEI resolution, and support for instruments that never have a ticker. 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 dense and long, but nearly every clause carries useful information about behavior, coverage, or caveats. It is front-loaded with the purpose and key usage instruction, and it organizes into recognizable segments (supported types, enrichment notes). It is not a concise one-liner, but the length is justified by the tool's complexity.

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?

For a tool with no output schema, the description is exceptionally complete. It explains what identifiers are returned, what happens when resolution is ambiguous or fails, how enrichment degrades, what inputs are accepted, and why the tool replaces multiple manual lookups. An agent has enough context to call it correctly in nearly any intended scenario.

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 baseline is 3. The description goes further by explaining the meaning of the type enum, what each identifier type means, and adding critical value-parameter nuance such as passing the exact issuer name for bonds and avoiding trailing security-class words. This meaningfully supplements 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 example queries and states the core purpose: resolving a user-spoken NAME into canonical/official identifiers that other tools require. It lists supported entity types and the specific identifier systems involved (SEC CIK, GLEIF LEI, OpenFIGI FIGI, RxNorm RxCUI), which clearly distinguishes it from sibling tools like entity_profile or compare_entities.

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 explicit guidance: 'Use FIRST whenever you have a name but need an ID.' It also provides detailed input-format instructions, including what not to pass for bonds. However, it does not explicitly name sibling tools it should be preferred over or state when to use an alternative, so it stops short of full when-to-use/when-not-to-use guidance.

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