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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, so the safety profile is covered; the description adds useful context beyond that — public FINRA source, no API key required, and the shape of what comes back. It does not mention the 12-row cap or pagination implications, which is the main remaining behavioral gap.

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 purpose sentence, then a scannable bulleted when-to-use list, then a one-line provenance note. No filler, no repetition of the title, and the size matches a simple 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?

Annotations cover read safety and an output schema exists, so the description need not explain returns (though it helpfully summarizes them). Missing pieces are pagination behavior (rows/start) for iterating results and any hint that search may return zero or ambiguous matches, which matters for a name-based lookup.

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 nested schema documents every parameter thoroughly (name examples, rows max 12, 0-based start, two-letter state, wholesaler_ids resolution rules), so the schema carries the load. The description only adds indirect hints — 'by name', 'distinguish by location' (state), 'territory map' (state/wholesaler scope) — and says nothing about pagination via rows/start or the cache/source_resource_id workflow.

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 and resource ('Search FINRA BrokerCheck for broker-dealer firms by name') and enumerates return fields (CRD, registration status, city, state, disclosure flag). The 'employer/firm' framing implicitly separates it from the individual-oriented SearchBrokerCheck and SearchIAPDIndividual siblings, but no sibling is named explicitly.

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?

'Use this tool when' followed by three concrete scenarios (getting a CRD number, disambiguating same-named firms by location, mapping BD firms in a state) gives an agent clear selection context. It stops short of stating when NOT to use it or naming SearchBrokerCheck/GetBrokerCheckDetail as the alternative for the detail/individual case.

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