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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so safety is covered structurally. The description adds value beyond that by enumerating the return payload (certificate number, city, state, total assets) and the scope limit (US banks only), which the annotations don't convey. It says nothing about result ordering or what happens when the query matches many banks, which is the main remaining 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?

Two tight sentences with zero filler: purpose and return fields first, then the workflow directive, then the optional filter. Every clause earns its place and the most decision-relevant content ("Use this first") is placed early.

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 carries the burden of describing results and does so explicitly. For a simple three-parameter read tool with full annotation coverage, nothing an agent needs in order 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 description coverage is 100%, so all three parameters are already documented, including the state code format and the note that a city name also matches. The description only restates the optional state narrowing, adding no syntax or semantics beyond the schema. Baseline 3 applies when the schema carries the parameter burden.

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 ("look up a US bank by name") and immediately names the key output ("FDIC certificate number"), which is what distinguishes it from the sibling analytics tools. It also gives concrete query examples ("Chase", "state street"), so an agent knows the input granularity without opening the schema.

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 first: every other tool needs the certificate" is explicit sequencing guidance that tells the agent to call this before deposit_pricing_decision, get_bank_profile, or any other sibling. It doesn't explicitly state when NOT to use it (e.g., to fetch full profile details, which is get_bank_profile's job), but the prerequisite framing covers the practical decision.

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