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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world scope, so the safety profile is covered. The description adds the useful constraint that the context is read-only and should be fetched once after sign-in, and signals the returned facets; it doesn't discuss auth failure behavior, which is a minor residual 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 sentences, zero filler, with the payload description front-loaded and the usage cue second. Every clause carries information.

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 an output schema present, the description needn't explain return values, and it correctly summarizes them at a high level instead. Combined with rich annotations and a no-arg schema, this is nearly complete; only the signed-out/error case is unaddressed.

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 tool takes zero parameters, so the baseline is 4 and there is no parameter meaning the description could add or omit. Nothing about argument semantics is left ambiguous.

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 ('Return') and resource ('the signed-in Proofable profile and its current read-only context'), then enumerates the payload (proof index, agents, permissions, verifier summary). That enumeration also separates it from siblings like proofable_agents_list or proofable_proofs_check, which each return one slice.

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 once after sign-in' gives an explicit timing cue and an implicit anti-pattern (don't poll it repeatedly), which is more than most definitions offer. It stops short of naming alternatives or when-not-to-call conditions, so it is clear context without full routing.

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