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

With no annotations provided, the description carries the full burden of behavioral disclosure. It clearly states the authentication requirement, the mutation scope (name only), and warns that start_login will not grant access to this tool. This is meaningful context beyond the schema, though it does not describe success/error responses.

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 compact and front-loaded, with the core purpose stated in the first sentence. Every sentence earns its place: the second sentence prevents misuse by clarifying immutability, and the ACCESS paragraph gives a necessary authentication instruction and a clear warning about start_login.

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 simple two-parameter update tool with no output schema, the description covers the essential operational context: what can be updated, what cannot be changed, and the authentication prerequisite. It is complete enough for an agent to call the tool correctly, though it doesn't elaborate on return values or error cases.

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 the baseline is 3. The description adds value by clarifying that the name parameter is the display name and is the only mutable field, while the profile/identity binding cannot be changed through this tool. This enriches the meaning of the name parameter beyond the schema's short 'New name for the Circle.'

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 opens with a specific verb and resource: 'Update a Circle's name.' It further distinguishes itself by stating that only the display name is mutable and that profile/identity binding is create-only, which separates it from creation or other update operations among the sibling tools.

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 provides clear context by requiring a Proof account and explicit authentication steps. It also gives an exclusion by warning that start_login does NOT open this tool, helping the agent avoid an incorrect access path. It does not explicitly name alternatives for other update scenarios, but the create-only binding note implies the boundary.

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