check_bookmark

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

No annotations are provided, so the description carries full responsibility for disclosing behavior. It states only that it checks and returns metadata, but does not mention whether the operation is read-only, what happens if the URL is not bookmarked, or any error cases. The safe verb 'check' implies read-only, but this is not explicitly stated.

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 concise sentence, front-loaded with the main verb and purpose. It is free of fluff and reads efficiently. While it is minimal, it communicates the core function without unnecessary words.

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?

The tool is simple with one fully described parameter and an output schema, so the description does not need to explain return values. However, it lacks context about edge cases (e.g., archival status, URL normalization) and does not explicitly differentiate itself despite siblings. It is minimally adequate but not richly complete.

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?

The input schema already fully describes the single parameter 'url' as 'URL to check,' giving 100% schema coverage. The description adds no extra context about formatting, validation, or URL requirements. With high schema coverage, a baseline of 3 is appropriate, even though the description does not enhance parameter understanding.

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 specific action: 'Check if a URL is already bookmarked and get metadata.' This distinguishes it from sibling tools like get_bookmark (which likely retrieves by bookmark ID) and search_bookmarks (which searches) by focusing on URL-based existence checking. The verb 'check' and resource 'URL/bookmark' are explicit.

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. It does not mention any prerequisites, exclusions, or recommend other tools for different scenarios. Users must infer usage solely from the purpose, but there is no explicit 'use this instead of...' context.

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