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

Beyond the annotations (write, non-idempotent, non-destructive, closed-world), the description adds real behavioral context: the return is a chained, signed decision entry attributed to the role and not GAIP, the call is free with no account, and inputs must be public and non-personal. It does not state repeat-call behavior explicitly, but the chained-entry framing plus the non-idempotent hint communicate the key trait.

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?

Four compact sentences, front-loaded with the use condition, then the key arguments, then the return and constraints. Every sentence carries information with no filler, though the parameter list slightly duplicates the schema.

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 9-parameter write tool with no output schema, the description covers the essential operational facts: what it returns, that it is a receipt only, and the public/non-personal input constraint. The absence of explicit idempotency/retry guidance is a minor residual gap given the annotations already flag non-idempotency.

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%, so every parameter is already documented in the schema, including enum values and hash length constraints. The description names proposal_sha256, decision, and agreement_id but adds no syntax or semantics beyond what the schema provides, so it sits at the baseline.

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 specific verb and resource: recording a role's decision (sign-off) on an agent's proposal, with the exact vocabulary of roles and decisions. It is clear what the tool does, though it never explicitly contrasts itself with siblings like witness_finding or witness_accept_terms, leaving the agent to infer the boundary.

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 this when a role ... decided on an agent's proposal" gives a clear trigger condition, and the named enums narrow when it applies. However, no alternative tool or exclusion is named, so the agent is not told which tool to use instead when the condition does not hold.

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