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

Annotations declare it read-only and idempotent, and the description adds substantial behavioral context beyond that: cascading internal lookups, graceful degradation if external sources are unavailable, ambiguous matches returning candidates, explicit unresolved identifiers, and cross-source labeling. 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 and dense, but every section (examples, supported types, edge cases, degradation behavior) earns its place for such a complex tool. It is structured with headers and front-loaded with examples, though it could be trimmed slightly without losing value. It is not a tautology; it is appropriately detailed.

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 there is no output schema, the description must explain return behavior, and it does: it mentions `figi_candidates` for ambiguous matches, `unresolved` for failures, and cascading steps. It covers multiple entity types, non-US issuers, and bond specifics. Nothing needed to call it correctly 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% already, but the description goes far beyond by explaining the exact meaning of 'value' for each type, including traps like trailing security-class words. It also clarifies the 'type' enum behavior. This adds significant value over the schema alone.

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 an explicit action (resolve name to canonical identifiers) with a specific resource (identifiers like CIK, ticker, LEI, RxCUI, FIGI) and gives many example queries. It also clearly distinguishes its scope from siblings by noting it supplies IDs that other tools require as input. No ambiguity about what it does.

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 instructs to 'Use FIRST whenever you have a name but need an ID.' It details when to use for company vs drug, gives example inputs, and even warns against passing full noun phrases for bonds. It clearly implies when not to use (when you already have the ID) and does not require inference.

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