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

No annotations and no output schema, so the description carries the full burden — and it does a reasonable job by enumerating the returned state categories (remaining signals/attestations this epoch, anchoring feasibility, mint price, contentRef limits) plus the 'with reasons' qualifier. It omits safety framing (read-only vs. stateful), what happens for an unknown/invalid keyId, and whether results are epoch-cached. A solid but not complete disclosure.

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 dense sentences, front-loaded with the outcome ('what one Key can do right now'), then the payload contents, then the workflow instruction. Every sentence earns its place; the only weakness is the unexplained domain jargon, which trades clarity for brevity.

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 and no annotations, the description must carry both payload shape and behavioral context. It covers the payload categories reasonably but leaves gaps: what happens on an invalid keyId, whether the call has side effects, and the meaning of Canon/contentRef for an agent without domain knowledge. Adequate, not complete.

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 single required parameter keyId has 0% schema description coverage, yet the description never mentions it — not its meaning, format, or how to obtain a valid key id (e.g., from z1n_get_key). 'One Key' implies a parameter exists but adds no semantics; the agent must guess what identifier the integer represents.

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 resource and scope: the actionable state of 'one Key right now, with reasons', and enumerates the payload (signals/attestations remaining, Canon anchoring, mint price, contentRef limits). It is clearly a composite read-state tool and is differentiated from siblings by the claim that it 'replaces combining four endpoints'. Docked one point because the core verb is vague ('What one Key can do') and heavy jargon (Canon, contentRef) is unexplained without prior context.

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?

Gives an explicit trigger: 'Read this before building any transaction', which tells the agent when in a workflow to call it. It also implicitly steers away from calling the four separate endpoints it replaces. There is no explicit 'when not to use' or named sibling alternative, so not a 5.

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