update_library_metadata_by_ids_merge

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

The annotations already convey readOnly=false, idempotent=true, and destructive=false, and the description adds no behavioral context beyond restating the endpoint. It does not disclose what happens to the merged items, whether the operation is reversible, or whether special permissions are needed. The description neither contradicts nor meaningfully extends the annotation profile.

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?

Four short lines, front-loaded with the purpose before the endpoint and args, with no filler words. Each line carries information, though the brevity borders on under-specification rather than disciplined conciseness.

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 an output schema and safety-relevant annotations, the description need not cover return values or idempotency, but it must explain a non-trivial 'merge' semantic and how the two parameters interact. It does neither, and offers no sibling differentiation, leaving the agent to guess when this tool is appropriate.

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 two 'Args' lines carry the entire burden of parameter meaning. They clarify that ids is a comma-separated list and that ids_query relates to item identifiers, but the definitions are shallow, largely restate the parameter names, and tension exists with the schema type for ids_query (array/null vs 'comma-separated list'). The relationship between ids and ids_query is never explained.

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 opens with a specific verb-resource pairing — 'Merge a metadata item' — and the endpoint URI '/library/metadata/{ids}/merge' reinforces the operation target. The word 'merge' distinguishes it from the large family of update_library_metadata_by_ids_* siblings (split, match, unmatch, refresh). However, it never explains what merging actually entails, leaving the semantics somewhat ambiguous.

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?

There is no guidance on when to use merge instead of sibling operations such as update_library_metadata_by_ids, split, match, or unmatch. No preconditions, no exclusions, and no description of the operation's effect are provided — a costly omission given the roughly 200 sibling tools listed.

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