Asset metadata

Returns the asset object with a fresh short-lived url for the content. Re-fetching always yields fresh URLs.

OpenAPI

````yaml /openapi-v2.yaml get /api/v2/assets/{id} openapi: 3.0.3 info: title: Comfy API v2 version: 2.0.0

description: |

The official, versioned HTTP API for running ComfyUI workflows from external applications: upload inputs, submit a workflow, observe execution, retrieve results.

Design principles:

Poll-first. Every capability is reachable via plain GET polling; the SSE stream is a live enhancement, never the source of truth.
Everything is resumable. Submission is idempotent; job state and outputs are retrievable by ID until expires_at.
UUID identity, content-addressed dedup. Assets are UUID-identified records over blobs keyed by a server-computed blake3 hash. The hash is nullable and may be computed lazily.
Follow links, don't build URLs. Responses embed follow-up URLs.

Additive changes only within v2; breaking changes require v3. servers:

url: http://127.0.0.1:8189 description: Self-hosted (comfy-api-proxy)
url: https://cloud.comfy.org description: Comfy Cloud
url: https://{deployment}.run.comfy.app description: Serverless deployment variables: deployment: description: >- DNS-safe deployment id (subdomain label). Staging uses {deployment}.stg.run.comfy.app. default: dep-1234abcd-56ef-7890-abcd-ef1234567890 security:
bearerAuth: []
{} tags:
name: assets description: UUID-identified records over content-addressed blobs.
name: jobs description: One execution of a workflow — durable, pollable, cancelable. paths: /api/v2/assets/{id}: get: tags:
assets summary: Asset metadata description: >- Returns the asset object with a fresh short-lived url for the content. Re-fetching always yields fresh URLs. operationId: getAsset parameters:
$ref: '#/components/parameters/AssetId' responses: '200': description: The asset. content: application/json: schema: $ref: '#/components/schemas/Asset' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '404': $ref: '#/components/responses/NotFound' '429': $ref: '#/components/responses/RateLimited' '500': $ref: '#/components/responses/UpstreamError' '503': $ref: '#/components/responses/DeploymentLookupUnavailable' components: parameters: AssetId: name: id in: path required: true schema: type: string example: 9f8a1c0d-2b3e-4f56-8a7b-1c2d3e4f5a6b schemas: Asset: type: object description: >- A user-owned record identified by a server-assigned UUID, backing an immutable blob whose content carries a server-computed blake3 hash. hash may be computed lazily: an asset record (and its retrievable bytes) can exist before its hash is filled in. On an output, job_metadata carries the labels its producing job was submitted with, so code holding only the asset knows which run it came from. It is absent for assets no job produced, for outputs of a job sent without labels, where the serving surface keeps no job labels, and when the labels could not be read: so job_id without job_metadata does not prove the job had no labels. A create whose file path and bytes match an existing output answers with that output, so its job_id and job_metadata are the output's. required:
id
hash
size_bytes
content_type
created_at
url
url_expires_at properties: id: type: string example: 9f8a1c0d-2b3e-4f56-8a7b-1c2d3e4f5a6b hash: type: string nullable: true description: 'blake3:<hex>; null while lazily computed.' example: blake3:9f8a1c0d... size_bytes: type: integer format: int64 example: 4816293 content_type: type: string example: image/png file_path: type: string nullable: true example: photo.png created_new: type: boolean description: >- On POST /api/v2/assets responses, distinguishes a brand-new blob (true) from a dedup hit against bytes the platform already had (false). On POST /api/v2/assets/from-hash responses, true means a new asset reference was created over existing bytes (201); false means an existing asset was reused (200). created_at: type: string format: date-time url: type: string format: uri description: Short-lived content URL (signed, or proxy-served). url_expires_at: type: string format: date-time expires_at: type: string format: date-time nullable: true description: >- Retention deadline for the asset itself (distinct from url_expires_at, the signed URL's validity). Null or absent means the asset is non-expiring. On a dedup-hit create response the deadline may be later than now + the requested/default retention: re-referencing content extends its retention, never shortens it. job_id: type: string nullable: true description: >- ID of the job that produced this asset. Absent for assets no job produced, such as a fresh upload. job_metadata: allOf:
$ref: '#/components/schemas/JobMetadata' description: >- The labels the producing job was submitted with, read through job_id on each read. Absent for assets no job produced, for outputs of a job sent without labels, where the serving surface keeps no job labels, when the job is gone, and when the labels could not be read: so job_id without job_metadata does not prove the job had no labels. JobMetadata: type: object description: >- The labels the job was submitted with, exactly as sent. Absent when it was sent with none. additionalProperties: type: string example: client: acme ErrorEnvelope: type: object description: | Shared error envelope with machine-readable codes. Core codes (v1): invalid_workflow (422), workflow_format_ui (422), missing_asset (422), hash_mismatch (409), blob_not_found (404), idempotency_key_reuse (422), upload_timed_out (422: an asset upload stopped sending or was too slow; retry from a faster connection), queue_full (429 + Retry-After), rate_limited (429 + Retry-After: the caller is past a request rate limit; retry), insufficient_credits (402), not_found (404), unauthorized (401), forbidden (403). Deployment-scoped surfaces add: deployment_not_ready (429 + Retry-After — the deployment can still reach ready; retry), deployment_unavailable (429 + Retry-After: the deployment is ready but its GPU provider is not taking work on it yet; retry), deployment_lookup_unavailable (503 + Retry-After, on any operation: the deployment the address names could not be looked up just now; nothing was done, so retry), database_unavailable (503 + Retry-After, only on a job submit: the job could not be saved just now and nothing was started, so retry), auth_unavailable (503 + Retry-After, on any operation: the credential could not be checked just now, which says nothing about the credential, so retry), output_unavailable (503 + Retry-After, only on a job status read: an output of the job could not be prepared just now; the job is unchanged, so retry after Retry-After, and report the job if it keeps answering), deployment_stopped (422 — terminal deployment state; a retry cannot succeed without operator action), invalid_request (422: a malformed asset upload or asset-from-hash field, or a jobs-list limit that is not a positive integer), validation_error (422, Cloud: an asset upload or asset-from-hash field was refused, e.g. a tag over the tag limits), content_blocked (451: content moderation flagged the asset's bytes) and sso_required (403: the key is valid, but the account must sign in through its organization's single sign-on, which does not accept this key). Comfy Cloud's asset upload adds invalid_content_type (422: the request is not multipart/form-data with a boundary), invalid_body (422: a malformed multipart body or upload field), validation_error (422: the platform refused the upload, for example an image over the size cap or a disallowed tag) and upload_busy (503 + Retry-After: the server is busy with other uploads and nothing was stored, so retry). Job labels add: metadata_invalid (422: a submitted metadata breaks a limit; details.key names the key, except for too many pairs, which has no details), metadata_not_supported (422: this surface keeps no job labels yet), invalid_metadata_filter (400) and invalid_cursor (400). A surface that does not list jobs yet answers not_implemented (501). A 429 is disambiguated by error.code alone; clients should treat any 429 + Retry-After as "back off and retry". required:
error properties: error: type: object required:
code
message properties: code: type: string example: invalid_workflow message: type: string example: 'Node 12 (KSampler): required input ''model'' is not connected' organization_id: type: string description: >- On sso_required: the organization whose single sign-on governs this key, the one that holds the account, else the one that holds the key's workspace. It is the organization query parameter of Comfy Cloud's single sign-on start; treat it as opaque. Absent when the organization is unknown, and on every other code. example: org_01HXYZEXAMPLE details: type: object nullable: true additionalProperties: true description: >- Machine-readable detail for the code. When it carries node_errors, that is keyed by node id and each value is a JobNodeError, the same shape as a job's error.node_errors, whether the refusal came at submit (for example unknown_node_class, a node class the deployment's build does not contain) or from ComfyUI after dispatch. With unknown_node_class errors it carries unknown_node_classes, the missing classes; with waits_for_browser errors, browser_wait_node_classes, the classes that wait for a browser. A submit refusal names at most fifty nodes. For invalid_node, invalid_inputs and invalid_class_type, when it found more than fifty, node_errors_truncated is true and malformed_node_count carries the full count; for waits_for_browser, browser_wait_node_count does. For unknown_node_class it names only nodes whose class is one of the at most ten listed in unknown_node_classes; when those nodes number more than fifty, node_errors_truncated is true and unknown_node_count is how many nodes have a listed class. Nodes whose class is past those ten are neither named nor counted. example: node_errors: '12': class_type: SomeCustomNode errors:
type: unknown_node_class message: >- this deployment's build does not contain the node class SomeCustomNode. unknown_node_classes:
SomeCustomNode responses: Unauthorized: description: >- unauthorized: missing or invalid credentials. A credential that could not be checked answers auth_unavailable (503) instead. content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' Forbidden: description: >- forbidden — authenticated but not allowed. On a serverless deployment, also sso_required — the key is valid, but the account must sign in through its organization's single sign-on, which does not accept this key; it can come back on any operation. content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' NotFound: description: 'not_found.' content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' RateLimited: description: >- rate_limited — the caller has exceeded a request rate limit for this account. Account/rate-scoped, not resource-specific — this can be returned even for a job, asset or deployment the caller doesn't own or that doesn't exist. headers: Retry-After: $ref: '#/components/headers/RetryAfter' content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' UpstreamError: description: >- upstream_error — an unexpected failure reaching or processing the request in this implementation's backing services. The message is always a generic, safe-to-display string; implementation detail (the specific upstream, its error text, transport failures) is never included here — see each implementation's own error-mapping notes. Every operation in this contract can fail this way. content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' DeploymentLookupUnavailable: description: >- On deployment-scoped surfaces, deployment_lookup_unavailable: the deployment this address names could not be looked up just now. The request was refused before it did anything (nothing was created, read, changed or canceled), so the same request can be sent again after Retry-After. Every operation at a deployment's address can answer this way. A job submit can also answer this 503 with database_unavailable: the job could not be saved just now and nothing was started, so the same request can be sent again after Retry-After. No other operation answers database_unavailable. On Comfy Cloud an asset upload can also answer this 503 with upload_busy: the server is busy with other uploads and nothing was stored, so the same upload can be sent again after Retry-After. Any operation can also answer this 503 with auth_unavailable: the credential could not be checked just now, so the same request can be sent again after Retry-After. A job status read can also answer it with output_unavailable: an output of the job could not be prepared just now, and the job is unchanged. A transient storage failure clears on a later read after Retry-After; an output whose stored address is broken answers it on every read until the platform repairs the output. headers: Retry-After: $ref: '#/components/headers/RetryAfter' content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' headers: RetryAfter: schema: type: integer description: Seconds to wait before retrying. securitySchemes: bearerAuth: type: http scheme: bearer description: >- Authorization: Bearer <credential>. The credential is one of: an account-scoped API key (comfyui-…), accepted on Cloud and serverless; a Comfy Cloud session JWT; or an OAuth access token issued for the Comfy Cloud resource. Which kinds a given deployment accepts is deployment configuration — an API key always works on Cloud and serverless, and a deployment that does not accept JWT bearers answers 401 with a message saying so. Self-hosted accepts unauthenticated requests by default and can be configured with a static bearer token.

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