Download an Existing Google Flow Job

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

Annotations only declare non-readOnly, openWorld, non-idempotent, non-destructive. The description adds substantive behavior: saves to a configured absolute directory, validates files, writes manifests, fails rather than guessing a mismatched asset, and does not trigger generation. It does not state overwrite/idempotency behavior on repeat calls, which is the main remaining gap.

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 tool's role and single-sentence constraint, then behavior. Slightly redundant in restating exactness ('exact asset identities' / 'fails instead of guessing'), but every sentence carries usable 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 one-parameter tool with no output schema, the description covers scope, side effects (directory writes, manifests), failure mode, and the non-generation guarantee. An agent can call it correctly; only idempotency/overwrite semantics on repeated downloads are unaddressed.

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% and the single jobId parameter is fully documented in the schema itself (UUID format, pattern, 'exact UUID returned by the generation'). The description reinforces exactness but adds no syntax or format detail beyond the schema, so the baseline 3 applies.

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+resource ('download an existing Flow job') and immediately differentiates the mechanism from siblings/categories: it uses recorded asset identities rather than gallery order, and explicitly rules out generic browser/computer-use tools.

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 condition for use ('the exclusive path to download an existing Flow job') and an exclusion ('never download through generic browser/computer-use tools', 'does not start a generation'). It does not name the specific flow_generate_image/flow_generate_video siblings that produce the jobId, but the surrounding guidance is strong.

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