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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), and the description usefully adds that the derivation is deterministic and root-scoped, which explains why idempotency holds. However, it does not clarify whether any binding is persisted/registered despite the 'bind' name, nor what happens if the agent is unknown or the pubkey mismatches.

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?

A single front-loaded sentence with no filler; the scope constraint ('under the shared root') arrives early. Density of unexplained internal terminology slightly reduces accessibility.

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?

An output schema exists, so return values need not be explained, and the annotations carry the safety semantics. Still, for a tool with two fully undocumented required parameters and no routing guidance among six siblings, the description leaves real gaps.

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%: neither agent_id nor pubkey has any documented format, encoding, or constraints. The description does not compensate at all — it never mentions the two required inputs, so an agent gets no guidance on pubkey encoding or agent_id shape.

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 uses a specific verb ('derive') and names the exact resource ('the canonical did:viridis identity for an agent'), which distinguishes it from siblings such as viridis_agent_attestation or viridis_certify. It loses a point because 'fleet R1 formula' and 'shared root' are internal jargon that an unfamiliar agent cannot resolve, and no sibling is explicitly contrasted.

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 statement of when to call this versus the alternatives that also involve identities or marks (viridis_agent_attestation, viridis_verify_mark), nor any prerequisite such as needing the shared root established first. The agent must infer usage entirely from the tool name.

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