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

The annotations already declare destructiveHint=true, non-idempotent behavior, and closed-world scope. The description adds meaningful operational context: human confirmation, permission checking, linking to a local contact, and the caveat that first messages still require recipient approval. It does not elaborate on what makes the action destructive or whether it is reversible, so it stops 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?

The description is four short sentences, front-loading usage and safety before mechanics and caveats. Every sentence contributes useful information, and the minor informal abbreviation does not impede understanding.

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 two-parameter mutation with an output schema and safety annotations already present, the description covers the key prerequisites, linking behavior, and post-accept caveat. An agent has enough context 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 100%, so both parameters are already documented. The description reinforces that invite_token comes from the invitation URL and contact_id represents the inviter locally, but it adds no syntax or constraints beyond 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 names a specific verb and resource: accepting a connection invitation, using invite_token, and linking it to contact_id. It is clearly distinct from connections.invite and connections.list in practice, though it does not explicitly contrast itself with those 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?

It gives a clear condition for use: when the human received a connection invitation and wants to accept it. It also adds an important prerequisite, confirming the person and requested permissions with the human first, but it does not mention alternatives or exclusions.

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