video-gen

name video-gen description AI video generation via Seedance, Kling, Gemini Omni, MiniMax H3, and MiniMax H3 Max. Use when the user wants to generate a video clip — text-to-video, image-to-video, first/last-frame transitions, reference-guided generation — or wants to modify / edit / extend an existing generated clip. user-invocable true Video Gen Submits one video generation job per call and returns a jobId . Job status and later check-backs belong to track_progress ; this skill does not place videos on the timeline automatically. When to Use Any time the user wants to generate a video clip — text-to-video, image-to-video, first-last-frame transition, reference-based generation, or generatively editing / extending an existing video (producing new generated footage based on a source clip; not timeline trimming). Models Model Reference Strengths seedance-2-5 references/seedance25.md Default. 4-30s, up to 50 multimodal references, audio-only reference, timestamp control, and mp4/mov output. Strongest Seedance choice for new generation, edit, and extend. seedance2 references/seedance2.md Seedance 2.0 full model. 4-15s, rich multimodal references, and up to 1080p output. seedance2fast references/seedance2.md Seedance 2.0 Fast — same inputs and 4-15s range as seedance2 , returns in minutes instead of ~ten, ~20% cheaper, capped at 720p . Use when the user is iterating and turnaround matters more than peak fidelity. seedance2mini references/seedance2.md Seedance 2.0 mini — same inputs and 4-15s range as seedance2 , ~50% cheaper, capped at 720p . Use for cheap drafts and high-volume batches where the full model's fidelity isn't required. kling references/kling.md Camera-control language via prompt; strong on fine emotional / performance control for character shots. 1080p via mode:"pro" . minimax-h3 references/minimax-h3.md MiniMax H3. 4-15s, 768p/2k, first/last frames, and up to 9 image + 3 video + 3 audio references (12 total). Strong multimodal reference following. minimax-h3-max references/minimax-h3-max.md MiniMax H3 Max. 5-15s, 480p/768p, text or first/last-frame generation. No reference mode or 2K output. omni references/omni.md Gemini Omni 1.1 Flash. Targeted edits/extensions via continueFrom , first/last frames, and cheap 360p drafts. 3-10s; 720p default, upscaled 1080p/4k. IMPORTANT: Before generating, READ the chosen model's reference for capabilities, input channels, modes, prompt structure, and model-specific behavior. Model Selection For a new generation , seedance-2-5 is the default . Only switch when one of: User explicitly named a model ("用 Kling", "use Kling", "用 Omni", "用 mini", "/kling") — switch, no need to re-ask. User explicitly asks for MiniMax H3 or needs combined image/video/audio reference guidance with optional 2K output — use minimax-h3 . User explicitly asks for MiniMax H3 Max or wants its highest-fidelity text/frame generation without multimodal references — use minimax-h3-max . Seedance clearly can't or won't do it well — when you hit a known case where Seedance struggles, propose switching to kling and confirm before submitting. User explicitly asked for a fast / cheap draft they expect to revise — propose omni (360p drafts, ≤10s, supports targeted edits) and confirm before submitting. User needs Seedance output at 1080p — prefer seedance-2-5 ; it and full seedance2 support 1080p. User wants Seedance's 2.0 inputs cheaply, or many clips at once, and is fine with 720p — propose seedance2mini (4-15s, ~50% of the 2.0 full-model cost) and confirm before submitting. User is iterating on 2.0-style output and cares about turnaround — propose seedance2fast (480p or 720p, 4-15s, ~80% of the 2.0 full-model cost, returns much sooner) and confirm before submitting. Otherwise stay on seedance-2-5 . For revising a clip that already exists , the choice is made in Step 4 — not here. A revision request is not a reason to change the default for future fresh generations. Omni 1.1 replaces the previous Omni choice; keep the omni alias and do not invent a second legacy choice. Access note: all eight models require ChatCut paid video-generation entitlement (subscription or paid credits). Never present another model as a free workaround for a subscription gate; offer free Motion Graphic animation instead when the user asks for a free path. Tool Params Param Values Default prompt video description (required) — model seedance-2-5 , seedance2 , seedance2fast , seedance2mini , kling , minimax-h3 , minimax-h3-max , omni seedance-2-5 durationSeconds seconds 5 ratio see model docs 16:9 resolution model-specific; H3: 768p/2k; H3 Max: 480p/768p; Seedance: 480p/720p/1080p; Omni: 360p/720p/1080p/4k 720p (H3 models: 768p) outputFormat mp4 , mov ( seedance-2-5 only) mp4 (generate); mov (edit/extend) taskMode generate , edit , extend ( seedance-2-5 or omni ) generate name descriptive asset name (required) — firstFrame project asset ref — lastFrame project asset ref — continueFrom video asset ref — omni only , source to edit/extend — Model-specific params (e.g., Kling mode , Seedance refImages / refVideos / refAudios ) — see the model's reference. Input Resolution firstFrame / lastFrame / refImages / refVideos / refAudios all take a project asset reference. Prefer a full UUID or short prefix from browse_assets ; asset://<id> and same-project asset URLs returned by asset tools are also accepted. Per-slot type: frame slots and refImages → image; refVideos → video; refAudios → audio. External URLs and base64 are not accepted. If the source is a public URL, download it into the sandbox workspace, import the local file through asset-import + push_asset , and pass the resulting asset id. Workflow Four-step loop. For each new generation, restart from Step 1 if the user's intent has shifted. Step 1 — Align scope with the user Before writing any prompt, align on three dimensions: Duration & segments — total length, how many shots, and whether they live in one clip or several. If the user has already stated a direction ("做一段", "in one video", "分别生成", "split into N shots", etc.), follow it — don't second-guess. Otherwise, surface the two paths and let the user pick: Multi-shot within one clip (see model ref) — single inference, subject / lighting / style physically consistent across sub-shots; fits a coherent narrative within the per-clip duration cap. Multiple clips — each clip is independently controllable and re-rollable, but identity and style continuity have to be carried by anchors; fits durations beyond the cap or hard scene breaks. Offer the trade-off; do not pick for the user. Content — what each clip depicts. Summarize back what you understood, segment by segment. When content is vague (e.g. "generate a video of a girl dancing"), the user typically hasn't specified one or more of: Subject : who / what is the main subject (appearance, outfit, defining features)? Action : what are they doing? (For talking / emotional shots, what micro-expression?) Scene : where — setting, time of day, environmental details? Lighting / color mood : what atmosphere? Camera : any shot-size / angle / movement preference? Style : visual style or reference (cinematic / anime / documentary / ...). Focus on the items that matter for this specific request and can't be safely inferred — don't turn this into a blank-filling exercise. Summarize the understood parts back to the user before proceeding. Consistency anchors — only when multiple shots reuse a character, object, or scene: identify which anchor (reference image or video) to pin across shots. For sourcing rules, see §Visual consistency across shots below. For each dimension, check the user's words: Clear — proceed. Ambiguous or missing — ASK the user. Do not guess, do not default to your own interpretation. A round-trip confirmation is cheaper than a wasted generation. What NOT to do Do not "tell then submit" — announcing "I'll make this as 2 clips" and immediately submitting is not alignment, it's a unilateral decision with announcement. Do not default to splitting a single-video request into multiple clips. A single clip can carry multiple sub-shots (see model ref), with subject / lighting / style physically consistent across them. Surface the trade-off, then let the user choose. Do not skip the ask because you think the answer is obvious. Hard overrides (user's explicit word wins) "one clip / single clip / 一条 / 一个镜头 / in 1 clip" → never split, even if the description is objectively long. "N shots / N 段 / N 个镜头" → generate exactly N. "use this image / 用这张图" → use as reference, don't substitute. Step 2 — Write the prompt See the chosen model's reference for prompt structure and param combinations (e.g., Seedance's 8-element structure and modes; Kling's prompt tips). Before submitting, check: name is a descriptive asset name — descriptive enough for the user (and you in later turns) to recognize this asset in the project library. Avoid vague names like "Untitled" or "clip 1". Param combination matches the user's intent — see the Modes section in the model's reference. Generated video audio is not a tool parameter. Seedance and Kling are submitted with audio enabled by the backend. On validation failure, read the error and fix the inputs — do not blindly retry the same invalid arguments . Step 3 — Submit one, wait, confirm Submit one generation job at a time. Unless the user explicitly asked for multiple clips in parallel, do not submit the next clip until the current one completes and the user has reviewed it. Parallel submission hides problems: if the first shot has drift or wrong framing, the user would rather redo it once than have several misaligned shots to discard. submit_video.ratio controls the generated asset only; it does not change the project timeline canvas. If the user requested a final output aspect ratio (for example "9:16 vertical" or "16:9 landscape"), set the timeline canvas to the same ratio with manage_timelines action=update (e.g. ratio:"9:16") before placing the completed asset. If the user asked for no black bars / full-bleed, pass fit:"cover" when setting the canvas or updating/adding the visual item. Do not use this skill for job management — use track_progress for an immediate status read and follow its later check-back guidance. After submitting, end your turn (tell the user the job was created) unless a follow-up task is already queued. When the job finishes, surface the result to the user for review before proceeding to the next shot. For Omni source edits, follow the first/middle/end frame review in its reference before claiming the requested change succeeded. Model-specific failure handling — see the model's reference. Step 4 — Iterate When the user wants a next clip, a revision, or a continuation, first decide what the existing clip is in the next call: The existing clip is… Path The thing being modified — a targeted change; preservation is not pixel-exact omni + continueFrom A source to re-generate from — new motion / camera, whole-clip style shift, extend, bridge seedance-2-5 + refVideos ; set taskMode for edit/extend Not reusable — the intent changed regenerate, restart at Step 1 A localized change defaults to omni + continueFrom . For an explicitly chosen Omni continuation use taskMode:"extend" + continueFrom ; for transitions between two images use firstFrame + lastFrame . Keep Seedance 2.5 as the general edit/extend path otherwise. Do not wait for the user to say "keep everything else" — "把气球改成黄色" / "remove the text in the corner" already means it. Route to seedance-2-5 only when the change genuinely needs re-inference (motion, camera, duration, whole-clip style), not because Seedance is more familiar. omni source edits/extensions require a project video of up to 10 seconds. For longer sources use seedance-2-5 + refVideos or ask to trim first. This integration is stateless: do not promise the upstream 40-second multi-turn workflow. No generative edit is lossless. Omni 1.1 supports upscaled 1080p/4k, but higher resolution does not guarantee detail or unchanged pixels. Review the result before replacing a timeline item; the original asset remains available. Then apply the standing rules: If it's the next shot in a multi-shot sequence — reuse the established anchor (see §Visual consistency across shots below for principles, model ref for flag-level details). If the user's feedback is ambiguous ("it doesn't feel right") — ask what specifically to change before regenerating.