fdic_summary

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds context about the data scope (by state or charter type) and the nature of the output (aggregate totals), which is useful. It does not disclose any edge cases like pagination limits or response format, but given the annotations cover the critical behavioral aspects, a 3 is appropriate.

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 two sentences with zero fluff. It front-loads the purpose and then gives a concrete use case. Every word contributes to the agent's understanding, making it highly efficient and well-structured.

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?

Given there is no output schema, the description does a reasonable job of indicating what the tool returns: 'total banks, deposits, assets by state/year.' It also clarifies the aggregation dimension (state or charter type). While it doesn't specify the exact JSON structure or pagination behavior, the description is sufficient for an agent to understand the tool's purpose and expected output. It's not fully complete (no mention of sorting or field customization), but the schema covers those parameters, so a 4 is warranted.

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 (limit, fields, offset, filters, sort_by, sort_order) have descriptive comments in the schema. The description itself does not add extra meaning beyond what the schema already provides; it merely references state/year in the text, which aligns with the filters example. With full schema coverage, the baseline of 3 is correct.

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 clearly states the tool's purpose: 'Get aggregate banking statistics — industry totals by state or charter type.' This specifies a concrete verb and resource, and the mention of 'industry totals by state or charter type' distinguishes it from sibling tools like fdic_search_institutions (which likely searches individual institutions) and fdic_failures (which covers failures). The overview metrics (total banks, deposits, assets) further clarify what it returns.

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?

The description provides a clear context for use: 'Useful for overview metrics: total banks, deposits, assets by state/year.' This implies the tool is for high-level aggregates rather than detailed record-level queries. However, it does not explicitly name alternative tools or state when not to use it, so it lacks the explicit exclusion/alternative guidance that would warrant a 5.

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