a4a_cosign_agreement

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

No annotations, so the description carries the burden, and it does so well: it discloses the mutual-signature semantics, that one signature makes nobody a party, and that the operation concludes the agreement. It does not mention auth requirements or failure modes, keeping it just short of a 5.

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?

Front-loaded with the core action, then rationale, then args/returns. Mostly tight, though 'thereby conclude it' and 'conclude a deal' slightly repeat the same idea. Every other sentence earns its place.

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-value detail is not required, yet the description still notes the return is the concluded agreement's ID that subsequent operations reference. Combined with the clear workflow and param source, an agent has everything needed to invoke it correctly.

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 coverage is 0% and only one param exists, so the description must compensate. It does: it tells the agent exactly where the agreement_id comes from (a4a_get_agreements) and its required state ('WAITING FOR YOUR SIGNATURE'), adding meaning well beyond the bare string type in the schema.

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+resource combination ('Sign an agreement') and states the outcome ('thereby conclude it'). It distinguishes the action from a4a_make_agreement and a4a_get_agreements by clarifying this is the second-party cosign step that finalizes a proposed deal.

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?

Explicitly states when to use this: when a proposal marked 'WAITING FOR YOUR SIGNATURE' appears in a4a_get_agreements. It names the sibling tool and the precondition, and warns that without this step two independent agents cannot conclude a deal.

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