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

With no annotations, the description carries the full burden of behavioral disclosure. It indicates that the tool manages allowed outbound calls, but it does not state whether the list is fully replaced, whether peers are validated, or how tokens are handled. The update semantics and side effects are unclear.

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?

The description is a single, front-loaded sentence with no redundancy. Every word contributes to the core meaning, making it easy to parse quickly.

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 mutation tool with two required parameters, no annotations, and no output schema, the description lacks essential context: how to specify the target instance, whether the peer list is replaced or merged, and what the expected response or error conditions might be. The description is too sparse to fully support correct invocation.

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 schema has 0% description coverage, so the description needed to explain the parameters. It only hints that peers are callable A2A agents by name; it never clarifies what 'id' refers to, what a peer 'url' represents, or what 'token' is for. This leaves an agent uncertain about how to construct a valid request.

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 clearly states the action ('Set'), the object ('the list of other A2A agents'), and the scope ('this instance is allowed to call by name'). This distinguishes it from sibling tools, which focus on instance lifecycle rather than peer configuration.

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?

No usage guidance is provided. The description does not mention prerequisites (e.g., the instance must already exist), when this should be used relative to other configuration tools, or any conditions or exclusions. The intended use must be inferred from the tool name and sibling context.

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