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

The annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive behavior; the description adds substantive context by disclosing graceful degradation (EDGAR identifiers still return if GLEIF/OpenFIGI are unavailable), ambiguity handling (`figi_candidates` instead of a false assertion), and the explicit `unresolved` field. There is no contradiction between the description and 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 front-loaded with examples, purpose, and a 'use FIRST' directive, and every later segment addresses a distinct aspect: input forms, per-type outputs, ambiguity, unresolved handling, and failure degradation. It is comprehensive but heavy on nested parentheticals and run-on phrasing, which reduces skimmability even though the length is largely earned by the tool's multi-source 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?

Given that there is no output schema, the description carries the full burden of explaining return behavior, and it does so thoroughly: per-type identifiers, source labels, ownership fields, `figi_candidates`, unresolved identifiers, graceful degradation, and even a concrete bond-issuer naming rule. An agent has enough context to decide when to call the tool and what to expect back.

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?

Although the input schema already documents both parameters well, the description adds meaning beyond the schema: it introduces ISIN as an accepted company input (absent from the schema), explains how ISIN resolves via GLEIF to the issuing legal entity, covers non-equity instruments, and details the drug-mode output with a pipeworx citation. This directly helps an agent construct a correct `value` in edge cases the schema does not mention.

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 states a clear action: resolving a user-spoken name to canonical/official identifiers that other tools require as input. It opens with concrete natural-language triggers ('ticker for…', 'CIK for…', 'LEI for…') and distinguishes supported types ('company' and 'drug'), making it easy to recognize when this tool applies and easy to separate from sibling tools like entity_profile.

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,' and it enumerates the accepted input forms and entity types, giving an agent a clear trigger condition. It does not, however, name alternative tools or state explicit exclusion cases, so it stops short of full 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.