check_block

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

No annotations are provided, so the description carries full burden. It states the tool checks for block existence but doesn't disclose behavioral traits like what 'exists' means (e.g., unidirectional vs. bidirectional blocking), error handling (e.g., if users don't exist), authentication needs, rate limits, or return format. This is inadequate for a tool with no annotation coverage.

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 appropriately sized and front-loaded: the first sentence states the purpose clearly, followed by parameter explanations. There's no wasted text, though the structure could be slightly improved by integrating parameter details more seamlessly.

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 no annotations, no output schema, and low schema description coverage (0%), the description is incomplete. It doesn't explain what the tool returns (e.g., boolean, block details, error messages) or behavioral aspects like idempotency or side effects, leaving significant gaps for agent understanding.

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. It adds semantic meaning by explaining that 'user_id' is 'The ID of the first user' and 'other_user_id' is 'The ID of the second user,' clarifying their roles beyond just being string parameters. However, it doesn't specify format (e.g., numeric vs. UUID) or constraints.

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: 'Check if a block exists between two users.' It specifies the verb ('check') and resource ('block'), but doesn't explicitly differentiate from sibling tools like 'list_blocks' or 'create_block/delete_block' beyond the checking vs. listing/creating distinction.

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 guidance is provided on when to use this tool versus alternatives. The description doesn't mention sibling tools like 'list_blocks' (which might list all blocks for a user) or explain prerequisites (e.g., whether users must exist). It only states what the tool does, not when it's appropriate.

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