flow_status

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

With zero annotations, the description carries the full burden, and it delivers richly. It discloses the zero-credit cost model, the local CDP-backed architecture (no API keys), IRREVERSIBLE delete semantics, the thumbnail S402 false-positive by design, and live-verified boundaries (image in-flight cancel returns 404; video cancel wire-verified but not live-submitted). This goes well beyond what structured annotations would typically provide.

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?

The description is long, but the tool genuinely implements six distinct modes within one schema, so the length is justified. Critical constraints (zero-credit, irreversibility, never-submits-generation) are front-loaded in the first sentence block. Minor deduction: the architecture/CDP explanation and multilingual triggers are secondary details that could sit lower without losing the core guidance.

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 tool with 8 optional params, 6 modes, and no output schema, the description is remarkably complete: it names the backend endpoints invoked (tRPC flow.share.shareMedia, POST /v1/flowMedia:cancelGeneration, POST /v1/flow:batchDeleteAssets), documents the share URL format, and gives expected status transitions (in_progress → retry_after_seconds, MEDIA_GENERATION_STATUS_CANCELED). The lack of an output schema pushes more responsibility onto the description, which it mostly meets; brief mention of the full snapshot fields and status=completed contract covers it.

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. The description adds genuine value beyond the schema: mutual-exclusivity relationships among mediaId/deleteMediaIds/shareMediaIds/cancelMediaIds, the batch-delete all-or-nothing behavior (S400 on unknown id), the download=false default for fast polling, and the cancel re-check expectation. These cross-parameter semantics are not expressible in the input schema, so the description earns an above-baseline score.

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 resource (Google Flow), a clear verb set (introspect/status/download/delete/share/cancel), and explicitly differentiates from siblings: 'NEVER submits generation — video/image submission goes through flow_generate_video / flow_generate_image.' The multi-mode nature is clearly delineated, and an agent can immediately tell this is the management/polling counterpart to the generation 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?

An explicit WHEN section lists the six trigger conditions (preflight, poll mediaId, fetch asset, check credits, clean up, share, cancel). The NEXT section describes the full generation-to-polling workflow with the sibling tool, and the description states exclusions ('NEVER submits generation'). Routing between this and the generation siblings is unambiguous.

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