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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the description's added value is the sourcing and auth context: 'FINRA BrokerCheck public API. No API key required.' That is genuinely useful operational detail. It stops short of disclosing latency, rate limits, or what a missing/unknown CRD returns, so it lands at 4 rather than 5.

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?

Front-loaded with the core action in the first sentence, then a scannable bulleted usage block, with provenance last. Efficient and well ordered; the indentation/blank-line formatting is slightly noisy but no sentence is wasted.

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 single-record retrieval tool with a full annotation set and a declared output schema, the description supplies everything needed to select and call it: the key input, where to get that input, and the scope of the response. Return-value detail is correctly deferred to the output schema.

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?

The description covers only the CRD parameter and reinforces 'Obtain from SearchBrokerCheck', which is helpful cross-tool routing. The remaining parameters (wholesaler_ids, source_resource_id, exclude_fillers, etc.) are left entirely to the schema, and the reported schema description coverage signal is 0%, so the description does not compensate for them.

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?

States a specific verb (Retrieve) and resource (full FINRA BrokerCheck profile for one individual) with explicit scope (by CRD number). It also enumerates what the profile contains (employment history, exams, licenses, disclosures), which separates it from SearchBrokerCheck, the lookup sibling.

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?

Provides a 'Use this tool when' block with three concrete trigger conditions, including the prerequisite 'You have a CRD (from SearchBrokerCheck)', which explicitly routes the agent to the sibling that produces the required input. No alternatives or exclusions are left to inference.

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