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

Beyond the annotations (non-readOnly, openWorld, non-idempotent), the description discloses the concrete long-video slot cap (max 8), the exact error condition (quota_exceeded), and the asynchronous semantics (returns job_id quickly, requires polling). This is operational context an agent cannot derive from the annotation flags alone.

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 tightly packed sentences: capability first, constraint and remediation second, workflow third. No filler, and the most important gating fact (slot cap) appears early rather than buried.

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?

With no output schema, the description still explains what comes back (job_id) and how to resolve it to a usable video_id. Combined with the quota failure path, an agent has everything needed to invoke this correctly on the first try.

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 100%, and the description's source list (YouTube, Twitch, Kick, direct links) duplicates the youtube_url schema description almost verbatim. The lang parameter, including its default, is not mentioned in the description at all. Baseline 3 applies since the schema carries the load.

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 ('Import a long video from a link') and enumerates accepted sources. It is clearly distinguishable from siblings like get_import_status and clip_video, which it names as downstream steps rather than alternatives.

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?

Gives explicit when-to-use guidance plus the failure path: on quota_exceeded, free a slot via list_videos and delete_video, then retry. It also spells out the follow-up sequence (poll get_import_status until video_id, then clip_video), leaving nothing to inference.

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