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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so 'Read-only and non-transactional' is a restatement of structured data rather than added context. It never explains what 'snapshot' implies for freshness/staleness or what 'public-safe' filters out, which would be genuinely new information.

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 front-loaded sentences with no filler beyond the redundant 'non-transactional' clause. Appropriately brief for a read tool, though brevity here shades into under-specification.

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?

No output schema exists and the description does not describe the returned snapshot shape, its freshness, or how `limit` shapes the result. An agent knows the tool is safe to call but not what it will receive or when to prefer it over its three siblings.

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 0 percent and the single `limit` parameter is never mentioned in the description. The schema supplies numeric bounds and a default but no semantic meaning for what is being limited (signals? rows? candidates?), and the prose does not compensate.

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 states a clear verb (Return) and a specific resource (the latest public-safe FAIE signal snapshot). It does not, however, differentiate this tool from siblings like get_faie_health or investigate_faie_evidence, so an agent can't route between them without opening each 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?

There is no when-to-use guidance, no statement of what situation calls for a signal snapshot versus the health or evidence tools. 'Read-only and non-transactional' is a trait, not usage guidance.

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