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

Annotations only provide readOnlyHint=false, which is minimal. The description adds meaningful behavioral context: it requires an Idempotency-Key, it only delivers data (does not execute or authorize payment), and it is conditional on recipient permission. This goes beyond the annotation and helps the agent understand side effects and prerequisites.

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 sentences with no filler. The core action is front-loaded, the prerequisite is stated, and the non-behaviors are listed compactly. Every 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?

The tool has an output schema, so return values are covered elsewhere. The description covers prerequisites, idempotency, and exclusions. The main gap is that it does not explain what 'bounded task data' means or how the capability string relates to the recipient's advertised capabilities, but the overall picture is sufficient for an agent 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 description coverage is only 25%, so the description must compensate. The description mentions 'bounded task data' and 'Idempotency-Key', which loosely maps to the task and request_key parameters, but it does not explain the capability or recipient_id semantics beyond what the schema patterns imply. It adds some context but not enough to fully compensate for the low coverage.

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 ('Deliver') and resource ('bounded task data to a recipient'), and distinguishes itself from task execution and payment authorization. It does not explicitly name a sibling alternative, but the scope is clear enough to separate it from accept_task, complete_task, and similar siblings.

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?

The description gives clear context: use it when the recipient has allowed you and advertises the capability. It also states what it does not do ('does not execute the task or authorize payment'), which helps an agent avoid using it for execution. It does not explicitly name alternatives, but the exclusions are strong guidance.

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