save_bookmark

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

With no annotations, the description must carry the behavioral load, and it does disclose two meaningful traits: page content is untrusted data and duplicate canonical URLs are rejected. It omits the return behavior, permission requirements, idempotency, and what happens to partial/blocked fetches, so significant gaps remain for a mutation tool.

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?

Three front-loaded sentences: purpose first, then the two constraints, then the parameter instruction. Dense but each sentence carries information; no filler.

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?

A 19-parameter write tool with no annotations, no output schema, and 0% schema description coverage needs far more than three sentences. The description never explains the metadata model, the distinction between relations and unresolved_relations, or the effect of fetch_status, leaving the agent under-equipped to call 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 0% across 19 parameters, yet the description explains only one (untrusted_web_metadata). The many enum fields (sensitivity, fetch_status, bookmark_kind, reading_status) and structural fields (relations, unresolved_relations, aliases) get no semantic guidance in either place, so the description fails to compensate for the coverage gap.

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 gives a clear verb+resource ("Save one enriched bookmark") and adds scope ("from supported, neutral metadata"). It does not, however, distinguish this from plausible siblings like capture or save_recipe, leaving the agent to infer which write path applies.

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?

Usage is implied rather than stated: "Pass untrusted_web_metadata straight through from the fetcher reply" tells the agent the expected calling flow, and "duplicate canonical URLs are rejected" signals a precondition. There is no explicit when-to-use-this-vs-alternatives guidance or statement of prerequisites.

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