UGC Video Ad Maker - ManyMotions

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

Annotations only cover the safety profile (readOnly=false, destructive=false, openWorld=true, idempotent=true); the description adds the materially important context they omit: credit consumption (250 per scene), a multi-minute runtime, and the auth/sign-in requirement. No contradiction with the annotations — the explicit user-consent gate is consistent with a non-idempotent-perception but idempotent-flagged start operation.

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 and the cost/consent gate in the second clause, then exclusions last — a sensible ordering. It is a dense multi-sentence block, but each sentence carries distinct information (action, gating, cost, polling, auth, scope, exclusions); only the trailing exclusion list runs slightly long.

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?

An output schema exists so return values need no explanation, and the description still supplies the operationally critical facts an agent needs: cost, runtime, how to poll, auth prerequisite, and the exact class of ads it applies to. Nothing needed 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 90% and six parameters carry enums with their own descriptions, so the schema does the heavy lifting and the baseline is 3. The description's only param-adjacent value is tying cost to scenes ('250 per scene'), which loosely connects to the duration→scene-count mapping already documented in the schema, so it does not meaningfully exceed the 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 concrete verb+resource — 'Start the AI production of a prepared UGC video ad' — and immediately scopes it to a new short AI video ad in the signed-in account. The pipeline description (strategy, script, keyframes, scene videos, final cut) makes the output unambiguous and clearly distinct from prepare_ugc_video_ad and get_ugc_video_ad.

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 sets the gating condition ('only after the user explicitly asked to generate'), names the alternative for progress tracking ('poll with get_ugc_video_ad'), and lists concrete exclusions (editing uploaded video, captions, real human creators, stills, logos, non-ad videos). This is as close to a complete when/when-not/alternatives map as a description gets.

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

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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, and the description reinforces rather than contradicts them. It adds genuine behavioral detail beyond the annotations: the 7-step progress model, the script appearing once written, and the MP4 URL only being returned when the final cut is ready.

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?

Two sentences, front-loaded with the core action ('Check the progress...') before the return-value detail. The parenthetical listing what progress looks like is dense but earns its place; no filler sentences.

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?

An output schema exists, so return values need not be spelled out, yet the description usefully previews the two key outputs (progress state and MP4 URL). It also anchors the tool to the signed-in account. The only real gap is the unexplained project_id, which is minor for a single-parameter tool.

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?

There is a single required parameter, project_id, with 0% schema description coverage, so the schema does not explain it. The description never mentions project_id or clarifies whether it is the run/project identifier or where to find it, leaving the parameter's meaning to inference from its name.

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: 'Check the progress of a video ad run' and 'return the finished MP4 URL'. It also scopes the operation to the signed-in ManyMotions account and implicitly distinguishes itself from generate_ugc_video_ad and prepare_ugc_video_ad by being the status/retrieval counterpart.

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?

The description gives clear context for when to call it (polling progress, fetching the final MP4) and explicitly excludes write behavior with 'it never starts or changes a run', which steers the agent toward the sibling generate/prepare tools for those actions. It stops short of naming those alternatives directly, so the routing is implied rather than explicit.

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

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

Adds real behavioral context beyond the annotations: no credits charged, no sign-in required, and the exact shape of what comes back (scene count, credits, link). The one unreconciled point is that annotations declare readOnlyHint=false and idempotentHint=false while the description reads as side-effect-free; the description never explains the residual server-side state (e.g. a stored brief) that justifies those hints, so a small transparency gap remains.

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 action and the return payload, then usage and exclusions. Three sentences, each doing distinct work, with no filler or repetition of the title.

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 9-parameter planning tool with an output schema, the description covers the action, the non-billing/non-auth behavior, the return contents, and the full exclusion boundary. Nothing an agent needs before calling is missing, and return-value detail is correctly delegated to 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 description coverage is 100%, so every parameter is already documented in-schema. The description only restates the optional parameter list in a parenthetical and adds no defaults, formats, or interaction rules beyond what the schema provides, so the baseline of 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 and resource ('Prepare a UGC video ad brief ... from the product description and target audience') and immediately clarifies the output ('Returns the plan: scene count, credits required and the ManyMotions link'). The 'Nothing is generated' clause functionally distinguishes it from the sibling generate_ugc_video_ad without the agent needing to open either 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?

Provides an explicit inclusion condition ('only for a new short AI video ad about a product, brand, app or service ... with an AI presenter and voice') and pairs it with a concrete exclusion list: editing uploaded video, captions on existing footage, real human creators, still images, logos, non-advertising videos. This is a textbook when/when-not pair.

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