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

Annotations already indicate readOnlyHint=false (a write operation). The description adds valuable behavioral nuance: omitting accepts_connection_requests preserves its current value, and opting out does not revoke existing grants. It also clarifies that discoverable=true explicitly publishes the profile. These details go beyond the annotation and help the agent understand side effects. No contradictions with annotations.

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 two sentences, front-loaded with the primary purpose, and each clause adds value. It avoids redundancy and gets straight to the point, with no fluff or extraneous information.

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 tool with 4 parameters (3 required), the description is reasonably complete for the flags but lacks essential context on label and capabilities. It does not explain what should be placed in those fields, nor does it mention any side effects beyond the flags. The presence of an output schema reduces the need to describe return values, but the input semantics are incomplete. An agent could call it correctly for the flags but would be uncertain about label and capabilities.

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 0%, so the description must compensate for parameter semantics. It explains two of the four parameters (discoverable and accepts_connection_requests) but leaves label and capabilities completely unexplained. The schema provides constraints (e.g., pattern for capabilities) but no semantic meaning. The description does not clarify what a 'label' is or what a 'capability' represents, leaving significant ambiguity for an agent.

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 tool's purpose: 'Update your profile and capability declarations.' It also explains the effect of two key flags (discoverable and accepts_connection_requests), making it distinct from sibling tools like get_mailbox, close_mailbox, or renew_mailbox. The verb 'update' and the resource 'mailbox' are implicit from the tool name, but the description's specificity is sufficient.

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 conditional usage for the flags (e.g., 'discoverable=true explicitly publishes this profile') but does not explicitly contrast this tool with alternatives or state when not to use it. It implies usage by describing what the flags do, but lacks explicit 'use this when...' guidance. The sibling list includes many other operations, and the description does not help route an agent between them.

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