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

Annotations already establish readOnly/openWorld=false/destructive=false, but the description adds real operational behavior: results are scoped to locations the connection can see, only the newest 1000 files/apps are searched, scanCapped:true signals truncation, and ordering is newest-first. It stops short of explaining how limit/offset interact with the scan cap, so a 4 rather than a 5.

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?

Front-loaded with the core purpose and filters, then behavior, then sibling routing in a tight sequence. It is dense and mostly earns its sentences, though the per-asset return field list slightly duplicates the output schema.

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 exists, return values need not be restated, yet the description still covers scope, cap behavior, ordering, app handling and where to go for playlist/layout data. Nothing an agent needs to invoke it correctly is missing.

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%, so the baseline is 3, but the description adds meaning the schema lacks: kind:"app" returns app instances with their appKey, and narrowing via kind or folderId is the remedy when scanCapped is true. That cross-parameter guidance pushes it above baseline.

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?

States a specific verb and resource (search the media library) and goes further by naming the filters (name, kind, folder, tag) and the cross-cutting use case (resolve names to asset ids before building playlists, casting or assigning). It is clearly distinguishable from siblings like list_items, get_playlist and search_screens.

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?

Explicitly routes the agent: use list_items for playlists/schedules/layouts and get_playlist for the contents of one playlist, and tells you to pass kind:"app" for apps only. The when-to-use and when-to-use-something-else conditions are stated directly.

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