info

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

With no annotations provided, the description carries the burden of behavioral disclosure. It clearly states the operation is a metadata retrieval, but it does not mention behavior on invalid IDs, authentication requirements, or what 'full metadata' includes. The output schema covers return shape, so the gap is moderate rather than severe.

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, front-loaded sentence that communicates the action, target, and required identifier with no wasted words. Every element earns its place.

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 get-by-ID tool with one required parameter and an output schema, the description covers the essential invocation context. It does not discuss error handling or exclusions, but given the low complexity and existing output schema, it is sufficiently 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?

Schema description coverage is 0%, so the description must compensate. It does by clarifying that item_id is the Jellyfin item ID and that it identifies a single library item, adding meaning beyond the schema's minimal 'Item Id' title. It does not specify format details, but for a single simple parameter this is adequate.

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?

Description uses a specific verb ('Return') with a clear resource ('full metadata for a single library item') and the exact identifier ('Jellyfin item ID'). It clearly differentiates from siblings such as search, sessions, libraries, and next_up, which serve different purposes.

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 implies the appropriate use case: call this when you already have a Jellyfin item ID and need full metadata. However, it does not explicitly state when not to use it or mention alternatives such as search for finding IDs first.

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