Atomic keyed changefeed snapshot materializer
Fold supplied ordered revision-checked put/delete events into a fresh complete keyed snapshot with tombstones and receipts, or return the first tentative-fold conflict without partial state. Valid conflicts are normal paid results; never reads or writes a database.
data-assurance · Operation ID: keyed-changefeed-materialize
Choose this operation when
- Preparing a complete next snapshot from caller-supplied records and events
- Keeping exact typed tuple identity and explicit revision arithmetic
- Inspecting an offline ordered event fold before separately authorized persistence
Outside this profile
- Live CDC ingestion, database CAS or transactions, cursor advancement or durable writes
- Historical event deduplication, exactly-once execution or authenticated event provenance
- Partial record patches, last-writer-wins, tombstone garbage collection or CRDT convergence
- Fetching sources, changing external state or executing supplied data
Exact release references
Static JSON contract · Markdown reference · Fixed example response
Complete input schema
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"type": "object",
"properties": {
"snapshot": {
"maxItems": 512,
"type": "array",
"items": {
"type": "object",
"properties": {
"key": {
"minItems": 1,
"maxItems": 4,
"type": "array",
"items": {
"anyOf": [
{
"type": "string",
"minLength": 1,
"maxLength": 128
},
{
"type": "boolean"
},
{
"type": "integer",
"minimum": -9007199254740991,
"maximum": 9007199254740991
}
]
}
},
"revision": {
"type": "string",
"maxLength": 24,
"pattern": "^[1-9]\\d{0,23}$"
},
"value": {
"anyOf": [
{
"type": "object",
"propertyNames": {
"type": "string"
},
"additionalProperties": {}
},
{
"type": "null"
}
]
}
},
"required": [
"key",
"revision",
"value"
],
"additionalProperties": false
}
},
"events": {
"maxItems": 256,
"type": "array",
"items": {
"oneOf": [
{
"type": "object",
"properties": {
"id": {
"type": "string",
"minLength": 1,
"maxLength": 128
},
"key": {
"minItems": 1,
"maxItems": 4,
"type": "array",
"items": {
"anyOf": [
{
"type": "string",
"minLength": 1,
"maxLength": 128
},
{
"type": "boolean"
},
{
"type": "integer",
"minimum": -9007199254740991,
"maximum": 9007199254740991
}
]
}
},
"expectedRevision": {
"type": "string",
"maxLength": 24,
"pattern": "^(?:0|[1-9]\\d{0,23})$"
},
"op": {
"type": "string",
"const": "put"
},
"value": {
"type": "object",
"propertyNames": {
"type": "string"
},
"additionalProperties": {}
}
},
"required": [
"id",
"key",
"expectedRevision",
"op",
"value"
],
"additionalProperties": false
},
{
"type": "object",
"properties": {
"id": {
"type": "string",
"minLength": 1,
"maxLength": 128
},
"key": {
"minItems": 1,
"maxItems": 4,
"type": "array",
"items": {
"anyOf": [
{
"type": "string",
"minLength": 1,
"maxLength": 128
},
{
"type": "boolean"
},
{
"type": "integer",
"minimum": -9007199254740991,
"maximum": 9007199254740991
}
]
}
},
"expectedRevision": {
"type": "string",
"maxLength": 24,
"pattern": "^(?:0|[1-9]\\d{0,23})$"
},
"op": {
"type": "string",
"const": "delete"
}
},
"required": [
"id",
"key",
"expectedRevision",
"op"
],
"additionalProperties": false
}
]
}
}
},
"required": [
"snapshot",
"events"
],
"additionalProperties": false
}
Complete output-envelope schema
{
"type": "object",
"required": [
"operation",
"version",
"result",
"provenance"
],
"properties": {
"operation": {
"const": "keyed-changefeed-materialize",
"type": "string"
},
"version": {
"const": "0.29.0",
"type": "string"
},
"result": {
"$schema": "https://json-schema.org/draft/2020-12/schema",
"oneOf": [
{
"type": "object",
"properties": {
"profile": {
"type": "string",
"const": "explicit-key-revision-fold-v1"
},
"status": {
"type": "string",
"const": "materialized"
},
"snapshot": {
"maxItems": 768,
"type": "array",
"items": {
"type": "object",
"properties": {
"key": {
"minItems": 1,
"maxItems": 4,
"type": "array",
"items": {
"anyOf": [
{
"type": "string",
"minLength": 1,
"maxLength": 128
},
{
"type": "boolean"
},
{
"type": "integer",
"minimum": -9007199254740991,
"maximum": 9007199254740991
}
]
}
},
"revision": {
"type": "string",
"maxLength": 24,
"pattern": "^[1-9]\\d{0,23}$"
},
"value": {
"anyOf": [
{
"type": "object",
"propertyNames": {
"type": "string"
},
"additionalProperties": {}
},
{
"type": "null"
}
]
}
},
"required": [
"key",
"revision",
"value"
],
"additionalProperties": false
}
},
"receipts": {
"maxItems": 256,
"type": "array",
"items": {
"type": "object",
"properties": {
"eventIndex": {
"type": "integer",
"minimum": 0,
"maximum": 255
},
"eventId": {
"type": "string",
"minLength": 1,
"maxLength": 128
},
"key": {
"minItems": 1,
"maxItems": 4,
"type": "array",
"items": {
"anyOf": [
{
"type": "string",
"minLength": 1,
"maxLength": 128
},
{
"type": "boolean"
},
{
"type": "integer",
"minimum": -9007199254740991,
"maximum": 9007199254740991
}
]
}
},
"previousRevision": {
"type": "string",
"maxLength": 24,
"pattern": "^(?:0|[1-9]\\d{0,23})$"
},
"revision": {
"type": "string",
"maxLength": 24,
"pattern": "^[1-9]\\d{0,23}$"
},
"op": {
"type": "string",
"enum": [
"put",
"delete"
]
}
},
"required": [
"eventIndex",
"eventId",
"key",
"previousRevision",
"revision",
"op"
],
"additionalProperties": false
}
},
"conflict": {
"type": "null"
}
},
"required": [
"profile",
"status",
"snapshot",
"receipts",
"conflict"
],
"additionalProperties": false
},
{
"type": "object",
"properties": {
"profile": {
"type": "string",
"const": "explicit-key-revision-fold-v1"
},
"status": {
"type": "string",
"const": "conflict"
},
"snapshot": {
"type": "null"
},
"receipts": {
"maxItems": 0,
"type": "array",
"items": {
"type": "object",
"properties": {
"eventIndex": {
"type": "integer",
"minimum": 0,
"maximum": 255
},
"eventId": {
"type": "string",
"minLength": 1,
"maxLength": 128
},
"key": {
"minItems": 1,
"maxItems": 4,
"type": "array",
"items": {
"anyOf": [
{
"type": "string",
"minLength": 1,
"maxLength": 128
},
{
"type": "boolean"
},
{
"type": "integer",
"minimum": -9007199254740991,
"maximum": 9007199254740991
}
]
}
},
"previousRevision": {
"type": "string",
"maxLength": 24,
"pattern": "^(?:0|[1-9]\\d{0,23})$"
},
"revision": {
"type": "string",
"maxLength": 24,
"pattern": "^[1-9]\\d{0,23}$"
},
"op": {
"type": "string",
"enum": [
"put",
"delete"
]
}
},
"required": [
"eventIndex",
"eventId",
"key",
"previousRevision",
"revision",
"op"
],
"additionalProperties": false
}
},
"conflict": {
"type": "object",
"properties": {
"eventIndex": {
"type": "integer",
"minimum": 0,
"maximum": 255
},
"eventId": {
"type": "string",
"minLength": 1,
"maxLength": 128
},
"key": {
"minItems": 1,
"maxItems": 4,
"type": "array",
"items": {
"anyOf": [
{
"type": "string",
"minLength": 1,
"maxLength": 128
},
{
"type": "boolean"
},
{
"type": "integer",
"minimum": -9007199254740991,
"maximum": 9007199254740991
}
]
}
},
"code": {
"type": "string",
"enum": [
"REVISION_MISMATCH",
"DELETE_NOT_LIVE",
"REVISION_EXHAUSTED"
]
},
"expectedRevision": {
"type": "string",
"maxLength": 24,
"pattern": "^(?:0|[1-9]\\d{0,23})$"
},
"observedRevision": {
"type": "string",
"maxLength": 24,
"pattern": "^(?:0|[1-9]\\d{0,23})$"
},
"observedState": {
"type": "string",
"enum": [
"absent",
"live",
"tombstone"
]
},
"tentativePrefixLength": {
"type": "integer",
"minimum": 0,
"maximum": 255
},
"observationScope": {
"type": "string",
"const": "tentative-input-fold"
}
},
"required": [
"eventIndex",
"eventId",
"key",
"code",
"expectedRevision",
"observedRevision",
"observedState",
"tentativePrefixLength",
"observationScope"
],
"additionalProperties": false
}
},
"required": [
"profile",
"status",
"snapshot",
"receipts",
"conflict"
],
"additionalProperties": false
}
]
},
"provenance": {
"type": "object",
"required": [
"inputSha256",
"outputSha256",
"deterministic",
"externalRequests"
],
"properties": {
"inputSha256": {
"type": "string",
"pattern": "^[a-f0-9]{64}$"
},
"outputSha256": {
"type": "string",
"pattern": "^[a-f0-9]{64}$"
},
"deterministic": {
"const": true
},
"externalRequests": {
"const": 0
}
}
}
},
"additionalProperties": false
}
Fixed example
One accepted fixed example, not a custom-input trial. No operation runs when this static page is requested.
Example input
{
"snapshot": [
{
"key": [
"a"
],
"revision": "1",
"value": {
"qty": 2
}
}
],
"events": [
{
"id": "p1",
"key": [
"a"
],
"expectedRevision": "1",
"op": "put",
"value": {
"qty": 3
}
},
{
"id": "d1",
"key": [
"a"
],
"expectedRevision": "2",
"op": "delete"
},
{
"id": "p2",
"key": [
"b"
],
"expectedRevision": "0",
"op": "put",
"value": {
"qty": 4
}
}
]
}
Example response
{
"operation": "keyed-changefeed-materialize",
"version": "0.29.0",
"result": {
"profile": "explicit-key-revision-fold-v1",
"status": "materialized",
"snapshot": [
{
"key": [
"a"
],
"revision": "3",
"value": null
},
{
"key": [
"b"
],
"revision": "1",
"value": {
"qty": 4
}
}
],
"receipts": [
{
"eventIndex": 0,
"eventId": "p1",
"key": [
"a"
],
"previousRevision": "1",
"revision": "2",
"op": "put"
},
{
"eventIndex": 1,
"eventId": "d1",
"key": [
"a"
],
"previousRevision": "2",
"revision": "3",
"op": "delete"
},
{
"eventIndex": 2,
"eventId": "p2",
"key": [
"b"
],
"previousRevision": "0",
"revision": "1",
"op": "put"
}
],
"conflict": null
},
"provenance": {
"inputSha256": "0806420b48aaad2e7df90f6c368d04a2f588e308b57e6536133b1b3593c84b21",
"outputSha256": "8e3b4cfcf12793cfa950f05dde67e059ad2da1b5ec7be8f17024463b28337204",
"deterministic": true,
"externalRequests": 0
}
}
Bounds and precision
JavaScript IEEE-754 numbers; use strings for large integer IDs/exact decimals where the schema accepts strings. No lossless numeric parsing.
{
"global": {
"requestBytes": 131072,
"responseBytes": 524288,
"jsonDepth": 32,
"jsonNodes": 20000,
"requestsPerMinute": 60,
"paidAttemptsPerMinute": 20,
"idempotencyHours": 24
},
"operation": {
"inputBytes": 100000,
"outputBytes": 300000,
"jsonNodes": 10000,
"depth": 20,
"profile": "explicit-key-revision-fold-v1",
"snapshotEntries": 512,
"events": 256,
"finalKeys": 768,
"keyComponentsPerTuple": 4,
"keyComponentVisits": 3072,
"identifierUtf8Bytes": 128,
"aggregateKeyTupleUtf8Bytes": 64000,
"revisionMaximum": "999999999999999999999999",
"foldSteps": 256
}
}
Complete schemas, descriptions and cross-field validation may impose additional limits.
Proposed price and protocol definitions
{
"unit": "one successful operation call",
"proposedNominalUsd": "0.006",
"sixDecimalTokenBaseUnits": "6000",
"subscription": false,
"includesPayerWalletOrNetworkFees": false,
"liveQuoteVerified": false,
"condition": "Actual SDK challenge is authoritative only within the caller's explicit authorization; configured six-decimal token peg is an operator assertion, not a conversion guarantee."
}
Protocol definitions: x402, mpp. MPP uses Tempo charge. Paid MCP execution is unsupported. All runtime readiness is not evaluated in this build.
API path templates, not endpoints on this documentation host
{
"x402": "/v1/x402/keyed-changefeed-materialize",
"mpp": "/v1/mpp/keyed-changefeed-materialize"
}
Required headers
{
"Content-Type": "application/json",
"Idempotency-Key": "random 16–128 character operation identifier"
}
Actual SDK challenge amount, asset, network, recipient and wallet costs must pass independent authorization. Preserve identical key, body, protocol and credential on retries; on PAYMENT_UNCERTAIN stop and reconcile.
Execution profile and provider conditions
{
"deterministic": true,
"externalRequests": 0,
"maxExternalRequests": 0,
"resultSnapshotPersisted": false,
"fixedExampleIsIllustrativeSnapshot": false,
"requiresPayment": true,
"supportsMcpExecution": false
}
Deterministic supplied-input operation with no external requests or stored request/result bodies. Payment infrastructure retains payment metadata and hashes.
Failure handling
- HTTP 400: Malformed JSON, missing/invalid idempotency key, or payment identifier mismatch Correct the request before payment
- HTTP 402: Payment challenge or rejected payment Use official protocol SDK; inspect payment outcome before another payment
- HTTP 409: Idempotency conflict, duplicate proof, or PAYMENT_UNCERTAIN Keep original key, body, and proof; reconcile uncertainty with operator; never blindly repay
- HTTP 413: Input or generated output too large Reduce input; no payment attempted for validation failure
- HTTP 415: Unsupported media type or compression Send uncompressed application/json
- HTTP 422: Schema or service-specific semantic validation failure Correct input using returned error code; no payment attempted
- HTTP 429: Request/payment-attempt rate exceeded Wait for rate limit window; preserve existing payment identity
- HTTP 503: Payment configuration/provider/state unavailable, or live DNS preparation failed before settlement Check readiness; DNS preparation failures may retry the identical key/body/credential only; uncertainty requires reconciliation
Declared requirements
Before any paid call, refresh the live operation contract and POST the complete bounded budgeted plan to the separate API's /preflight. Unknown requirements block selection; compatible preflight is not permission to spend.