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

Annotations cover the safety profile (readOnly, idempotent, non-destructive), and the description adds substantial context beyond them: that identical companies are issued multiple times by different issuers and are not duplicates, that sources differ in authority (issuer catalogues vs aggregator observations with no KYC gate or custody claim), that targetArea is audience description not eligibility, and that absent yield/minimum/risk fields are absent rather than zero.

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 purpose and the core caveats are front-loaded before the long source enumeration, and the three numbered points are structured and information-dense rather than padded. It is long, but most of the length carries decision-relevant content for an identity-lookup tool.

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?

An output schema exists, so return format needn't be explained, and the description still supplies the interpretive guidance the agent needs (multiple issuances, source authority tiers, empty-vs-zero semantics). Nothing needed to call or interpret this tool 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 description coverage is 100%, so all six parameters (including enum values and pagination via offset/nextOffset) are already documented in the schema. The description adds only light framing (issuer comparison is the useful part, identity-data caveat) and no new syntax or format detail. Baseline 3 is appropriate.

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?

Opens with a specific question the tool answers (does a tokenized version of a company/ETF/bond exist and from which issuer) and states the search keys (company name, ticker, ISIN). It is clearly distinguishable from siblings like search_yield_products or get_country_registers.

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?

Explicit imperative: 'Use this BEFORE saying a stock is not available on-chain.' It also explicitly routes rate-bearing instruments to search_yield_products, and warns the agent to report the issuer rather than a bare existence claim. When-to-use and when-to-use-something-else are both stated.

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