add_bookmark

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

Beyond annotations (destructiveHint=false, idempotentHint=true, openWorldHint=true), the description adds critical behavioral details: bookmarks are private, stored server-side, not public records, no bookmark-record URI, and keyed by post URI. It also discloses authentication and rate limiting. 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 concise and well-structured: purpose first, then privacy, constraints, authentication, related tools, and rate limiting. Every sentence adds value without redundancy.

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 simple tool with two parameters, the description is fully complete. It covers input validation, behavior (idempotent, no-op for duplicates), privacy, authentication, and references to sibling tools. The output schema exists but isn't necessary to explain.

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 coverage is 100%, baseline 3. The description adds meaning beyond the schema by explaining that uri must be an AT-URI of a post and that cid is optional and auto-resolved. This context helps agents understand parameter constraints and defaults.

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: privately bookmarking a post on AT Protocol. It distinguishes itself from siblings by specifying that bookmarks are private and not public records, and mentions related tools (remove_bookmark, get_bookmarks) for alternative actions.

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 usage guidance: only posts can be bookmarked, bookmarking an already-bookmarked post is a no-op, and authentication is required. It mentions siblings for removal and listing, offering clear context for when to use this tool vs alternatives.

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