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

The description goes far beyond the annotations by disclosing internal cascading lookups, graceful degradation of LEI/FIGI enrichment, explicit unresolved identifiers, and ambiguity behavior returning figi_candidates. It also clarifies that non-equity instruments without tickers still resolve, which is important non-obvious behavior.

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 it earns most of its length with dense, high-value detail for a complex tool. It is front-loaded with trigger phrases and uses a supported-types breakdown, though some parenthetical asides could be tightened without losing meaning.

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?

With no output schema, the description must explain what the agent can expect from return values, and it does: identifiers labeled by source, unresolved IDs stated explicitly, ambiguity handled via figi_candidates, drug results including RxCUI/ingredient/brand, and graceful failure under enrichment outages. Nothing essential for correct invocation appears 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?

Even though the schema already documents both parameters well, the description adds substantial meaning beyond it: the value parameter accepts ISIN input not mentioned in the schema, ticker vs name search behavior is explained, and the bond-issuer-only guidance prevents a realistic misuse. This is meaningful value over the structured 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 user phrasings and a clear verb-resource pairing: resolve a spoken name to canonical official identifiers. It distinguishes itself from sibling tools like entity_profile and compare_entities by framing this as the identifier-lookup step that feeds other tools, not a profile or comparison operation.

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?

It explicitly says 'Use FIRST whenever you have a name but need an ID,' which is a strong when-to-use signal. It does not name sibling alternatives or state when not to use it, but the description's trigger examples and input restrictions make the usage context clear.

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