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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuinely useful context that annotations don't: dollar amounts are in thousands and ratios are percentages. However it says nothing about what 'recent' means (time window, ordering), which is the key behavioral question for this tool.

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?

Three short sentences, front-loaded with the purpose, no filler. Minor redundancy: '(FDIC)' and '(Source: FDIC.)' restate the same fact and could be merged.

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 simple one-optional-param read tool this covers source and units, which is the important part. With no output schema, though, the description gives no hint of what fields come back or over what time window 'most recent' is measured, leaving a real gap.

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% and the single optional `limit` parameter is fully documented in-schema ('Max rows (default 25)'). The description adds no semantics beyond that, so the baseline 3 applies.

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?

Names a specific resource (bank failures) and scope (most recent, FDIC-sourced), which distinguishes it reasonably well from siblings like failures_by_year and failures_dashboard. It stops short of explicitly stating how it differs from those siblings, so it isn't a 5.

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 only usage signal is the phrase 'most recent', which implies 'use this for latest failures' but never states when to pick this over failures_by_year or failures_dashboard. No exclusions, prerequisites, or alternative routing are given.

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