# canvas.capture
mutation write
Use when the requested change exactly matches canvas.capture; read the current state first when a version or identifier may have changed.
## Before calling
- Authenticate as the accountable Enhance person.
- Use only resource identifiers returned by an earlier capability result or supplied by the person.
- Reuse clientToken only when retrying this exact mutation input.
## Input
Show complete JSON Schema
```json
{"$schema":"https://json-schema.org/draft/2020-12/schema","type":"object","properties":{"canvasRef":{"type":"string","minLength":1},"waitMs":{"default":1500,"description":"Additional local polling after the server returns an active job; render creation retains its existing bounded HTTP deadline.","type":"integer","minimum":0,"maximum":5000},"baseVersion":{"type":"integer","exclusiveMinimum":0,"maximum":9007199254740991},"source":{"type":"object","properties":{"kind":{"type":"string","const":"recording"},"recordingId":{"type":"string","format":"uuid","pattern":"^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$"},"atMs":{"type":"integer","minimum":0,"maximum":9007199254740991}},"required":["kind","recordingId","atMs"],"additionalProperties":false},"previewJobId":{"type":"string","format":"uuid","pattern":"^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$","description":"The successful canvas_render job whose pixels you inspected at this exact recording time and canvas version."},"placement":{"type":"object","properties":{"kind":{"type":"string","const":"below-source"}},"required":["kind"],"additionalProperties":false}},"required":["canvasRef","baseVersion","source","previewJobId","placement"],"additionalProperties":false}
```
### Example
Show example input
```json
{
"canvasRef": "00000000-0000-4000-8000-000000000010",
"baseVersion": 1,
"source": {
"kind": "recording",
"recordingId": "00000000-0000-4000-8000-000000000010",
"atMs": 500
},
"previewJobId": "00000000-0000-4000-8000-000000000010",
"placement": {
"kind": "below-source"
},
"waitMs": 1500
}
```
## Result
Returns a typed canvas.capture result from the Enhance API without transport-specific prose.
- `operation` (required): Returned field operation.
- `state` (required): Returned field state.
- `requestedVersion` (required): Returned field requestedVersion.
- `source` (required): Returned field source.
- `attachment` (required): Returned field attachment.
- `result` (required): Returned field result.
- `failure` (required): Returned field failure.
- `warningCount` (required): Returned field warningCount.
- `warnings` (required): Returned field warnings.
Show complete result JSON Schema
```json
{"$schema":"https://json-schema.org/draft/2020-12/schema","type":"object","properties":{"operation":{"type":"object","properties":{"kind":{"type":"string","const":"canvas-render"},"canvasId":{"type":"string","format":"uuid","pattern":"^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$"},"jobId":{"type":"string","format":"uuid","pattern":"^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$"}},"required":["kind","canvasId","jobId"],"additionalProperties":false},"state":{"type":"string","enum":["queued","running","succeeded","failed","cancelled","expired"]},"requestedVersion":{"type":"integer","exclusiveMinimum":0,"maximum":9007199254740991},"source":{"type":"object","properties":{"kind":{"type":"string","const":"recording"},"recordingId":{"type":"string","format":"uuid","pattern":"^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$"},"atMs":{"type":"integer","minimum":0,"maximum":9007199254740991}},"required":["kind","recordingId","atMs"],"additionalProperties":false},"attachment":{"type":"string","enum":["pending","committed","not_confirmed"]},"result":{"anyOf":[{"type":"object","properties":{"recordingId":{"type":"string","format":"uuid","pattern":"^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$"},"atMs":{"type":"integer","minimum":0,"maximum":9007199254740991},"screenId":{"type":"string","format":"uuid","pattern":"^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$"},"screenNodeId":{"type":"string","minLength":1},"viewport":{"type":"object","properties":{"width":{"type":"integer","exclusiveMinimum":0,"maximum":9007199254740991},"height":{"type":"integer","exclusiveMinimum":0,"maximum":9007199254740991}},"required":["width","height"],"additionalProperties":false},"box":{"type":"object","properties":{"x":{"type":"number"},"y":{"type":"number"},"width":{"type":"number","exclusiveMinimum":0},"height":{"type":"number","exclusiveMinimum":0}},"required":["x","y","width","height"],"additionalProperties":false},"version":{"type":"integer","exclusiveMinimum":0,"maximum":9007199254740991},"alreadyPresent":{"type":"boolean"}},"required":["recordingId","atMs","screenId","screenNodeId","viewport","box","version","alreadyPresent"],"additionalProperties":false},{"type":"null"}]},"failure":{"anyOf":[{"type":"object","properties":{"reason":{"type":"string","enum":["VERSION_CHANGED","TARGET_NOT_FOUND","TARGET_INVALID","OUTPUT_TOO_LARGE","READINESS_TIMEOUT","SOURCE_FAILED","BROWSER_CRASH","CAPTURE_FAILED","CONVERSION_FAILED","PREPARATION_FAILED","UPLOAD_FAILED","WORKER_UNAVAILABLE","CANCELLED","EXPIRED","INTERNAL"]},"phase":{"type":"string","enum":["queued","claimed","grant","navigate","document","sources","fonts","layout","target","capture","serialize","compile","commit","upload","complete"]},"message":{"type":"string","minLength":1,"maxLength":500},"retryable":{"type":"boolean"},"sourceId":{"anyOf":[{"type":"string","minLength":1},{"type":"null"}]}},"required":["reason","phase","message","retryable","sourceId"],"additionalProperties":false},{"type":"null"}]},"warningCount":{"type":"integer","minimum":0,"maximum":9007199254740991},"warnings":{"type":"array","items":{"type":"string"}}},"required":["operation","state","requestedVersion","source","attachment","result","failure","warningCount","warnings"],"additionalProperties":false}
```
### Example result
Show example result
```json
{
"operation": {
"kind": "canvas-render",
"canvasId": "00000000-0000-4000-8000-000000000010",
"jobId": "00000000-0000-4000-8000-000000000010"
},
"state": "queued",
"requestedVersion": 1,
"source": {
"kind": "recording",
"recordingId": "00000000-0000-4000-8000-000000000010",
"atMs": 500
},
"attachment": "pending",
"result": null,
"failure": null,
"warningCount": 0,
"warnings": []
}
```
## Recovery
- BAD_REQUEST: correct the named fields and call again.
- UNAUTHORIZED: restore Enhance authentication, then retry once.
- FORBIDDEN or NOT_FOUND: check the supplied resource and selection; do not substitute unrelated content. Ask for corrected access or scope if needed.
- CONFLICT: read the current resource, merge the intended change, and retry with its version.
- INTERNAL: run Enhance diagnostics, report the failure, and stop repeating the call.
## Continue with
- Read the affected canvas resource to confirm the result.
## Versions
Compatibility: `219dfc283ee61d5bf1305c451a464c8d2e9b5de80191b78b773f547a51867d61`.
Minimum tested versions: Enhance CLI and MCP runtime 0.1.40, plugin 1.0.38, Node.js 24. No older floor is published.