jellyfin_library_add_path

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

With no annotations, the description carries the full burden and does disclose meaningful behavior: the path is translated through Jellyfin container mounts and must exist on both host and container sides. It says nothing, however, about the dry-run/apply workflow that governs whether anything actually changes, nor about required permissions, which is a notable gap 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?

Two tight sentences, front-loaded with purpose followed by path semantics and the scan note; no filler. It could have spent a few words flagging the dry-run default, but as written it is efficient and well-ordered.

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 6-parameter mutation tool with no annotations and no output schema, the description covers purpose, path handling, and post-scan behavior, but omits the safety-relevant apply/planHash contract even though it is central to how the call behaves. Adequate but with a clear gap given the absence of annotations.

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 high (83%), so 3 is the baseline, and the description adds real meaning beyond the schema: the path can be given as a host path (translated through container mounts) or a container path, and must exist on both sides. The schema only says 'folder, absolute (host or container path)', so the dual-existence and translation semantics are a genuine addition.

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 states a specific verb and resource ('Add a folder to an existing Jellyfin library'), and the word 'existing' implicitly separates it from jellyfin_library_create, which makes a new library rather than adding a path. It is clear and specific, though it never names a sibling outright, so it stops short of a 5.

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 largely implied by the purpose sentence, and 'Optionally scans the library afterwards' mildly routes around jellyfin_scan. However there is no explicit when-to-use/when-not guidance against jellyfin_library_create, jellyfin_task_run, or tdarr_library_add, so alternatives are left to inference.

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