video_check

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

The description adds behavior beyond the annotations: it discloses the cost model ('Free: the video was paid for when it was started, and checking costs nothing') and the polling semantics that justify idempotentHint=true. It also describes both success and failure outcomes (saved path vs. status/failure reason). It does not discuss filesystem write location details or timeout interaction with wait_seconds, which keeps it from 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 action, followed by cost and retry notes, then parameter and return details. The Args/Returns blocks are slightly redundant with the schema and the existing output schema, but they are short and each sentence carries actionable information.

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 two-parameter polling tool with an output schema already defined, the description covers the essential context: what it retrieves, why it's free to re-poll, how to poll, and what the response contains. Remaining gaps (units/ranges for wait_seconds, where the .mp4 is saved) are minor given the output schema.

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 0%, so the description carries the full burden and mostly succeeds: it explains that 'id' is 'The id returned by video_generate or video_edit' and that 'wait_seconds' is how long 'to keep waiting in this call (default 120) before returning the current status'. Units, valid ranges, and what happens at wait_seconds=0 are not stated, leaving a small gap.

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 concrete verb+resource pair ('Fetch a video ... and save it as an .mp4') and ties it to the specific producer tools (video_generate / video_edit) whose outputs it resolves. An agent can distinguish this from video_stitch, video_edit, and jules_status without opening a schema.

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 a clear trigger ('a video that video_generate or video_edit started but had not finished rendering when they returned') and explicit retry guidance ('Call it again with the same id if the video is still rendering'). It stops short of naming explicit exclusions or routing to a specific alternative sibling for the not-yet-ready case, so it is strong but not exhaustive.

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