> ## Documentation Index > Fetch the complete documentation index at: https://developer.usewarp.net/llms.txt > Use this file to discover all available pages before exploring further. # Verify a proof > Verifies a Groth16 proof off-chain against the proof's stored verification key. With `onchain: true`, also calls `verifyProof` on the proof's deployed verifier contract (allow-listed chains only). Enforces the proof's policies: value rules, a nonce signal (`kind: "nonce"`) that must equal the supplied nonce, and a nullifier signal (`kind: "nullifier"`) that can only be accepted once per proof. Attestation circuits also declare `kind: "project_ref"` (must equal the stored value) and `kind: "registry_nonce"` (enforced by the on-chain registry). A malformed policy fails closed (`policy: "invalid_policy"`, `valid: false`). Returns a signed receipt (compact JWS, EdDSA) that you can verify with the keys from the JWKS endpoint. Only the owning project's secret key can verify its proofs. ## OpenAPI ````yaml /openapi.json post /v1/zk/proofs/{proofId}/verify openapi: 3.0.3 info: title: Warp API version: 1.0.0 description: >- Public Warp API: hosted checkout sessions for Pay with Warp, hosted ZK proof verification, and Warp Verify attestation checks. contact: name: Warp Support email: support@usewarp.net license: name: MIT url: https://opensource.org/licenses/MIT servers: - url: https://api.usewarp.net description: Production security: - bearerAuth: [] tags: - name: Checkout sessions description: Create and track hosted checkout sessions. - name: ZK verification description: Verify Groth16 proofs against circuits deployed from the Warp Platform. - name: Attestations description: Public Warp Verify attestation checks. - name: Health description: Service status. paths: /v1/zk/proofs/{proofId}/verify: post: tags: - ZK verification summary: Verify a proof description: >- Verifies a Groth16 proof off-chain against the proof's stored verification key. With `onchain: true`, also calls `verifyProof` on the proof's deployed verifier contract (allow-listed chains only). Enforces the proof's policies: value rules, a nonce signal (`kind: "nonce"`) that must equal the supplied nonce, and a nullifier signal (`kind: "nullifier"`) that can only be accepted once per proof. Attestation circuits also declare `kind: "project_ref"` (must equal the stored value) and `kind: "registry_nonce"` (enforced by the on-chain registry). A malformed policy fails closed (`policy: "invalid_policy"`, `valid: false`). Returns a signed receipt (compact JWS, EdDSA) that you can verify with the keys from the JWKS endpoint. Only the owning project's secret key can verify its proofs. operationId: verifyZkProof parameters: - name: proofId in: path required: true description: ZK proof ID from the Warp Platform. schema: type: string requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/ZkVerifyRequest' responses: '200': description: Verification result content: application/json: schema: $ref: '#/components/schemas/ZkVerifyResponse' '400': description: Invalid request content: application/json: schema: $ref: '#/components/schemas/Error' example: error: code: invalid_request message: 'amount_usd: Number must be greater than 0' '401': description: Missing or invalid secret key content: application/json: schema: $ref: '#/components/schemas/Error' example: error: code: unauthorized message: Invalid API key '404': description: Not found (or owned by another project) content: application/json: schema: $ref: '#/components/schemas/Error' example: error: code: not_found message: Resource not found '409': description: The proof has no verification key yet (`proof_not_ready`). content: application/json: schema: $ref: '#/components/schemas/Error' '429': description: Rate limit exceeded content: application/json: schema: $ref: '#/components/schemas/Error' example: error: code: rate_limited message: Too many requests. Retry after the window resets. '502': description: >- On-chain verification was requested but the chain RPC did not respond (`onchain_unavailable`). content: application/json: schema: $ref: '#/components/schemas/Error' components: schemas: ZkVerifyRequest: type: object required: - proof - public_signals properties: proof: $ref: '#/components/schemas/Groth16Proof' public_signals: type: array items: type: string description: >- Public signals as decimal strings. The count must match the circuit and each value must be below the BN254 scalar field modulus. nonce: type: string pattern: ^[0-9]{1,78}$ description: >- Decimal nonce from the create-nonce endpoint. Required when the proof declares a nonce signal; it must equal that public signal. Otherwise optional: it is consumed but reported as `unbound`, because the proof itself does not commit to it. onchain: type: boolean default: false description: Also call `verifyProof` on the deployed verifier contract. ZkVerifyResponse: type: object properties: valid: type: boolean proof_id: type: string checks: type: object properties: offchain: type: boolean onchain: type: object properties: chain_id: type: integer contract_address: type: string result: type: boolean nonce: type: string enum: - ok - missing - used - expired - mismatch - unbound description: >- `ok`: the nonce is the proof's nonce signal and was consumed. `unbound`: consumed, but the circuit has no nonce signal (replay protection is advisory only). `mismatch`: the nonce does not equal the nonce signal. `missing`: unknown nonce, or none supplied when the circuit requires one. Omitted when no nonce was supplied and none is required. Anything other than `ok` or `unbound` makes `valid` false. policy: type: string enum: - ok - mismatch - n/a - invalid_policy description: >- `n/a` when the proof has no value rules. `invalid_policy` when a stored policy entry is malformed; the result is then never valid. nullifier: type: string enum: - ok - reused description: >- Present when the proof declares a nullifier signal and every other check passed. `reused` means the nullifier was already accepted for this proof, and `valid` is false. verified_at: type: string format: date-time receipt: type: string description: >- Compact JWS (EdDSA, Ed25519, `typ: warp-verify-receipt+jws`) over a `ZkReceiptClaims` payload. Verify the signature with the JWKS endpoint, then check `aud`, `exp`, `nonce` and `nonce_bound`, and remember `jti` if you need single-use receipts. Error: type: object required: - error properties: error: type: object required: - code - message properties: code: type: string description: >- Machine-readable error code: `invalid_request`, `unauthorized`, `not_found`, `proof_not_ready`, `onchain_unavailable`, `rate_limited` or `internal_error`. example: invalid_request message: type: string description: Human-readable description. Groth16Proof: type: object required: - pi_a - pi_b - pi_c description: Proof object as produced by snarkjs `groth16.fullProve`. properties: pi_a: type: array items: type: string pi_b: type: array items: type: array items: type: string pi_c: type: array items: type: string protocol: type: string enum: - groth16 curve: type: string enum: - bn128 securitySchemes: bearerAuth: type: http scheme: bearer description: >- Your project secret key: `sk_test_...` (testnet) or `sk_live_...` (mainnet). Use it only on your server. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.