Block a user

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

The description restates the title and adds no behavioral context beyond 'from contacting you'. While annotations include idempotentHint and openWorldHint, the description fails to disclose consequences like effects on existing conversations, reversibility, or whether the user is notified.

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 sentence with no filler, front-loading the core action. It is appropriately economical, though it sacrifices detail for brevity.

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?

Given the two-parameter schema and lack of output schema, the description is too sparse to provide adequate context for correct invocation. It leaves the optional 'accountId' parameter unexplained and does not clarify what 'blocking' entails in practice.

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?

With schema_description_coverage at 0%, the description must explain the parameters. It does not mention 'user' or 'accountId' at all, leaving their formats, purpose, and necessity completely undocumented.

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 'Block a user from contacting you' uses the specific verb 'block' with a clear resource ('a user') and a scope ('from contacting you'). This clearly distinguishes the tool from siblings like 'mute_peer' (which silences notifications) and 'ban_user' (which typically operates in a group/channel context).

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 no guidance on when to use this tool versus alternatives such as 'unblock_user', 'mute_peer', or 'ban_user'. It simply states the action without any context about suitable scenarios or exclusions.

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