# Asset Generation > Use Assets for brand-safe image or video generation, human picker UI, search/list/export actions, and cross-app asset selection. Use when a visual needs to be generated, refined, found, or handed off to another app. - Skill: `builderio/asset-generation` (Agent Skill) - Install (CLI): `npx skillmds@latest add builderio/asset-generation` - Raw SKILL.md: https://api.skillmd.com/api/skills/builderio/asset-generation/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: Builder.io (https://skillmd.com/u/builderio) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/builderio/asset-generation --- # Asset Generation ## Rule Use the Assets app when a workflow needs reusable brand media, a human picker, or generated image/video assets that another app can reference by ID and URL. ## Visual authority and brief Assets produces media; it does not invent a replacement brand language. Before generating, resolve the user's explicit subject, audience, message, format, and must-preserve constraints, then the active library, preset, or linked design system and its custom instructions, then approved Creative Context references. Impeccable-inspired guidance is a quality lens for composition, hierarchy, restraint, and finish — never a reason to override those sources. Compile the request into a short art-direction brief: visual role, subject, composition and crop, palette or material treatment, lighting or medium, exact visible text if any, semantic constraints, and exclusions. Classify the slot as `produce` (new media), `direct` (an existing approved asset), or `semantic` (a UI/icon/diagram the caller should build with its own primitives). Do not generate a decorative photo where the caller needs a semantic graphic. If brand context is missing, make the result clearly exploratory rather than claiming a brand match. ## Choose The Path - Use `generate-asset` when a person should get newly generated, on-brand image candidates and choose the winner in the inline picker. It matches a library when `libraryId` is omitted, generates candidates, returns the picker filtered to those run IDs, and works in in-app chat plus external MCP hosts. - Use `open-asset-picker` when a person should browse, search, or select an existing asset inside an embedded picker, or when you want the picker to handle generation itself. It still opens `/library` with the iframe/bridge contract. The normal human Library workspace is `/library` and `/library/:id`. Pass `mediaType: "image"` by default, or `mediaType: "video"` for video libraries. - Use unattended actions when the agent already knows what to do: `search-assets`, `list-assets`, `import-style-from-url`, `generate-image`, `generate-image-batch`, `generate-video`, `refresh-generation-run`, and `export-asset`. - In chat, consume composer `@` references as structured generation inputs: `brand-kit` maps to `libraryId`, `template` maps to `templateId`, and `media-type` chooses image generation versus video generation. If no mention is available, use `view-screen`, `list-libraries`, and `list-templates` to choose explicit args. - Use Templates when the user asks for a repeatable output format like social image, blog hero, or diagram. Call `list-templates` and pass `templateId` through generation/refinement actions. Templates may be global or associated with one brand kit; only associated templates can pin images, skeletons, or a canonical logo. `*-generation-preset` actions are deprecated aliases. - Use generation sessions when another person needs to continue improving a candidate. Sessions carry the brief, preset, active asset, feedback, and run IDs without requiring the original chat thread. - Use chat-driven `restyle-image` and `edit-image` for preserving subjects, applying library style, and making targeted changes. Do not surface separate restyle, edit, or quality-tier buttons in host UIs. - Use browser/deep-link fallback when the host cannot render MCP Apps inline (CLIs and code editors like Claude Code and Codex). Surface the returned picker link. When the user opens it, they can either click an asset — the page auto-copies a short handoff summary for them to paste back into chat — or simply tell you which one in words (e.g. "use image A" / "the second one"). Both are first-class; don't insist on the paste-back if they just name the pick. ## Image Workflows 1. Read the `creative-context` skill and retrieve visual references separately from factual evidence. Respect `contextMode: "off"`, pinned packs, and the exact reuse ladder before generation: approved native asset unchanged, compose approved pieces, lightly adapt a real example, condition generation on narrow references, then net-new only when the relevant corpus is empty. 2. For human-in-the-loop generation, call `generate-asset` first and preserve the returned picker/candidate metadata. For unattended generation, pick or match the library with `list-libraries` or `match-library`. If the user wants a default look rather than a brand library, call `list-library-presets` and then `create-library-from-preset`; the resulting library is editable and reusable like any other library. 3. For one asset, call `generate-image`; for multiple independent slots, call `generate-image-batch` with stable `slotId` values. 4. Image generation actions are synchronous. After `generate-image` or `generate-image-batch` returns, use its compact `images` / asset summaries directly; do not call `get-generation-run`, `refresh-generation-run`, or regenerate just to verify image runs. Use `get-asset` for full asset details and the audit-run actions for prompts, references, and settings. A result with `draftPendingApproval: true` came from a kit the user can draft in but not save into. Offer the candidate and say it needs a kit editor to be saved; `save-generated-image` will refuse, so do not call it or retry. Video carries the same marker on the initial async reply and on every `refresh-generation-run` result, so it survives the poll. 5. For template-backed work, pass a mentioned or selected `templateId`; for handoff work, pass `sessionId`. 6. Let the server choose a small deterministic reference set unless the user named exact assets. Canonical style anchors come from `assetLibraries.settings.canonicalStyleAssetIds` and `assets.metadata.isStyleAnchor`; they must remain subordinate to explicit library, preset, and per-run constraints rather than introducing a second visual language. 7. Pass `tier: "fast"` for exploration, `tier: "best"` for final/high-value output, or `tier: "auto"` when there is no clear preference. - Model/ratio compatibility: Gemini image models accept any `aspectRatio`, but `gpt-image-2` supports only `1:1`, `2:3`, and `3:2`. When the user needs another ratio (16:9, 9:16, 4:5, 21:9, …), pick a Gemini model rather than `gpt-image-2` — an unsupported pairing is rejected upstream. Source of truth is `supportedAspectRatiosForModel` / `MODEL_ASPECT_RATIOS` in `shared/api.ts`. 8. Direct generation returns `id`; picker selections return `assetId`. Preserve that asset identifier with `runId`, `previewUrl`, `downloadUrl`, and `embedUrl`. Preserve the immutable `contextPackId` and reuse labels on both generation run and output-asset metadata; rendered pixels are not provenance. 9. Use `refine-image` for feedback on an existing asset, `edit-image` for targeted changes, and `restyle-image` with `subjectAssetId` and `styleStrength` for subject-preserving brand restyles. 10. If a designer will take over, call `create-generation-session` or `update-generation-session`, then `prepare-generation-session-continuation` when they want a chat preloaded with the session context. For short vague prompts, enhance conservatively with library style context while preserving the user's original prompt in run metadata. If a public website is the style source, call `import-style-from-url` first so the library keeps the hydrated browser-derived design brief. Use `analyze-collection-style` when a collection needs upgraded vision brand analysis from image references before generation. Brand QA scoring and best-of-N selection are deferred. Generation success confirms a run and its provenance, not visual quality or brand match. Report the selected library, preset, style anchors, and whether the result used an Assets-grounded or fallback path. Claim a quality evaluator only when one actually ran. ## Video Workflows 1. Call `generate-video` with `16:9` or `9:16` and relevant image references. 2. Poll `refresh-generation-run` until the run completes and returns a video asset. 3. Use `export-asset` when another app needs a download URL or artifact type. ## Cross-App Use - Hosted default: connect `https://assets.agent-native.com/_agent-native/mcp`. Do not put shared secrets in skill files. - Local customization: run `npx @agent-native/core@latest app-skill launch --local` from the Assets app-skill manifest, or pass `--into ` for editable source. - For MCP callers, `generate-asset` is the portable first choice because the same MCP App picker renders inline in Agent-Native chat, ChatGPT, and Claude when the host supports MCP Apps. Include exact `assetId`, `runId`, media type, and URLs in the final response so the caller can attach or embed the media. Include `presetId` and `sessionId` when present. ## Don't - Do not call image/video providers directly from another app. - Do not treat `images` as the app identity; the app id is `assets`. - Do not use picker UI for unattended generation when direct actions are enough. - Do not use copyrighted screenshots or named studio/brand image sets as preset references. Use broad textual guidance and user-provided references instead.