Agent Output Verifier

io.github.mglbagiv0.3.2更新於 Oct 1, 2026

Independently verify an agent's output before you pay.

已驗證Streamable HTTP可網頁執行Security & MonitoringAI & MLDeveloper Tools

概覽

AI 產生的概覽

讓助理依 JSON Schema 與自訂規則檢查其他代理的結構化輸出，回傳通過/失敗、評分、修正提示與簽章憑證。

功能
透過託管的 Streamable HTTP 端點提供兩個 MCP 工具：verify_schema 依呼叫端提供的 JSON Schema 與選用規則，對結構、格式、數值範圍與跨欄位規則（例如各行小計加總必須等於總計）做確定性檢查；get_verification_record 依 agent_id 查詢某個代理的信任分數。驗證結果包含通過/失敗、檢查通過百分比、修正提示，以及可用服務公開金鑰驗證的 Ed25519 簽章證明與憑證。compact 模式只回傳摘要、憑證欄位與簽章。
適用情境
適合在助理或工作流程收到其他代理或賣方產出的結構化資料時，在採用或付款前做一次獨立且帶簽章的檢查。賣方也可在提交前用它驗證自己的輸出並附上證明。
執行需求
遠端託管服務，不需本機安裝、帳號或註冊。MCP 端點透過 Streamable HTTP 存取。每個工具每天有 3 次免費呼叫；超過後需以 x402 v2 在 Base 或 Solana 上支付 USDC，付款資訊放在 MCP 請求 _meta 中的 x402/payment，或在 REST 上使用標準 x402 付款標頭。需要能連線至該服務的網路。
安裝前請注意
付費呼叫會花費 Base 或 Solana 上的 USDC（標價為每次驗證 0.02、每次分數查詢 0.01，實際價格以 x402 清單與 Payment-Required 回應標頭為準），因此涉及錢包與付款授權。提交的輸出、Schema 與規則會傳送給第三方託管服務。agent_id 是呼叫端自行提供且未經認證的標籤，信任分數不能當作身分證明。依賴憑證前應先以公開金鑰驗證其簽章。

安裝

在 SourceWeft 中

  1. 開啟 儀表板中的 Agent Output Verifier，將其新增到工作區。
  2. 為需要使用其工具的對話啟用該服務。

Web executable，透過 Streamable HTTP。 遠端服務在工作區中設定後即可從網頁執行環境執行。

其他 MCP 客戶端

把它新增到你客戶端的 mcpServers 設定中。

{
  "mcpServers": {
    "agent-output-verifier": {
      "type": "http",
      "url": "https://fastapi-service-5ag4.onrender.com/mcp"
    }
  }
}

README

Agent Output Verifier

Independently verify an agent's output before you pay.

Independent, deterministic checks of structure, formats, ranges and cross-field rules, such as "line totals must equal the total," against your own requirements, written in standard JSON Schema plus optional rules. Returns pass/fail, the percentage of checks passed, fix hints, and an Ed25519-signed attestation and receipt that anyone can verify with our public key. Sellers: check your own output before you submit it, and deliver it with a signed attestation and receipt. No signup: pay per call with x402 v2, in USDC on Base or Solana. 3 free calls a day through MCP.

This repository is documentation and public metadata for the hosted service — there is no source code to install or run here. The service itself is a live API at https://fastapi-service-5ag4.onrender.com.

Endpoints

PurposeEndpoint
MCP (Streamable HTTP)https://fastapi-service-5ag4.onrender.com/mcp
Verify an output (REST)POST https://fastapi-service-5ag4.onrender.com/verify/schema
Look up an agent's trust score (REST)GET https://fastapi-service-5ag4.onrender.com/score/{agent_id}
Agent card (discovery)GET https://fastapi-service-5ag4.onrender.com/.well-known/agent-card.json
x402 discovery manifestGET https://fastapi-service-5ag4.onrender.com/.well-known/x402
llms.txtGET https://fastapi-service-5ag4.onrender.com/llms.txt
Interactive API docsGET https://fastapi-service-5ag4.onrender.com/docs

Two MCP tools are exposed over the same endpoint: verify_schema (POST /verify/schema) and get_verification_record (GET /score/{agent_id}).

Pricing and networks

Paid per call with x402 v2, in USDC, on either network below — no account or signup required:

RoutePriceNetworks
POST /verify/schema$0.02 USDCBase (eip155:8453), Solana (solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp)
GET /score/{agent_id}$0.01 USDCBase (eip155:8453), Solana (solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp)

/.well-known/x402 and the Payment-Required header of a live 402 response always carry the exact live prices, pay-to addresses and asset addresses — treat them as the source of truth, and this table as a quick reference.

Free trial

Each MCP tool carries its own free-trial allowance: 3 free calls per day, available over MCP. After that, a call requires an x402 payment carried in the MCP request's _meta under x402/payment, or a standard x402 payment header on REST.

Verifying a receipt, step by step

Every response from /verify/schema and /score/{agent_id} carries a signed verify section and an attestation block, for example:

json
"verify": {  "public_key_url": "https://fastapi-service-5ag4.onrender.com/.well-known/agent-card.json",  "key_version": "v1-2026-09c",  "canonicalization": "RFC 8785 (JCS)",  "hash_algorithm": "SHA-256",  "service": "Agent Output Verifier",  "mcp": "https://fastapi-service-5ag4.onrender.com/mcp"},"attestation": {  "algorithm": "Ed25519",  "key_version": "v1-2026-09c",  "timestamp": "2026-10-01T01:01:09.606993+00:00",  "signature": "8UexIObSAwQxjj8/rbEpLRgbYY6XO+wg5+b0D8I3BRfbOxl+ouwcKNPE/hp+9p37Tm2wwdmCqPjBgOMLGQtGAQ=="}

Nothing but the response itself and verify.public_key_url is needed:

  1. Fetch the public key. GET the agent-card at verify.public_key_url. Its capabilities.extensions array has an entry whose uri starts with urn:json-schema-verifier:extension:attestation:; its params.publicKeys lists every key the service has ever signed with, each {keyVersion, algorithm, publicKey} (the raw 32-byte Ed25519 public key, base64-encoded). Pick the entry whose keyVersion equals response.attestation.key_version.
  2. Rebuild the signed document. It's a JSON object with exactly these five keys:
    json
    {  "context": "json-schema-verifier/verify-schema-attestation/v1",  "algorithm": "Ed25519",  "key_version": "<attestation.key_version>",  "attested_at": "<attestation.timestamp>",  "response": { "...": "the full response, with the attestation field removed" }}
    context is json-schema-verifier/verify-schema-attestation/v1 for /verify/schema responses, or json-schema-verifier/trust-score-attestation/v1 for /score/{agent_id} responses.
  3. Canonicalize it with RFC 8785 (JCS): UTF-8 bytes of the JSON document above, object keys sorted recursively, no insignificant whitespace, numbers printed the way ECMAScript prints them (1.0 becomes 1).
  4. Verify the Ed25519 signature (response.attestation.signature, base64-decoded) over those canonical bytes, using the public key from step 1.
  5. Check the four receipt hashes, each SHA-256 over the RFC 8785 (JCS) canonical JSON of the named value: output_hash (of submitted_output), schema_hash (of expected_schema), rules_hash (of {"bounds": ..., "rules": ...}), and request_hash (of the whole request as parsed, full detail only). Recompute them yourself and compare — this is what binds the receipt to the exact data that was checked.

A minimal Python verifier, using only the standard library plus cryptography:

python
import base64, jsonfrom decimal import Decimalfrom cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PublicKey
def es_number(x: float) -> str:    """A float exactly as ECMAScript / RFC 8785 (JCS) print it (1.0 -> "1", 1e-7 -> "1e-7")."""    if x == 0:        return "0"    sign = "-" if x < 0 else ""    digits_tuple = Decimal(repr(abs(x))).as_tuple()    digits = "".join(map(str, digits_tuple.digits)).rstrip("0") or "0"    n = len(digits_tuple.digits) + digits_tuple.exponent  # position of the decimal point    k = len(digits)    if k <= n <= 21:        body = digits + "0" * (n - k)    elif 0 < n <= 21:        body = digits[:n] + "." + digits[n:]    elif -6 < n <= 0:        body = "0." + "0" * (-n) + digits    else:        e = n - 1        body = digits[0] + ("." + digits[1:] if k > 1 else "") + f"e{'+' if e >= 0 else '-'}{abs(e)}"    return sign + body
def canonical(v) -> str:    if isinstance(v, bool):        return "true" if v else "false"    if isinstance(v, float):        return es_number(v)    if isinstance(v, dict):        return "{" + ",".join(f"{canonical(k)}:{canonical(v[k])}" for k in sorted(v)) + "}"    if isinstance(v, list):        return "[" + ",".join(canonical(x) for x in v) + "]"    return json.dumps(v, ensure_ascii=False)  # covers None, int, str
def verify(response: dict, public_key_b64: str, context: str) -> bool:    att = response["attestation"]    body = {k: v for k, v in response.items() if k != "attestation"}    message = canonical({        "context": context,        "algorithm": att["algorithm"],        "key_version": att["key_version"],        "attested_at": att["timestamp"],        "response": body,    }).encode("utf-8")    key = Ed25519PublicKey.from_public_bytes(base64.b64decode(public_key_b64))    try:        key.verify(base64.b64decode(att["signature"]), message)        return True    except Exception:        return False

Tested against both receipts in the worked example below — both verify True.

Worked example: invoice verification

Both calls below are genuine, live, paid calls against the production service — real x402 payments on Base, settled on-chain, with the resulting signed receipts shown exactly as received. Both are independently verifiable: fetch the agent-card above, confirm key_version: v1-2026-09c is listed, and verify each attestation.signature with the steps above.

1. Draft invoice — fails on a cross-field rule (detail: "full")

Request:

json
{  "task_id": "invoice-7731-draft",  "agent_id": "test-seller-invoice-agent",  "expected_schema": {    "type": "object",    "required": ["invoice_id", "currency", "line_items", "total"],    "properties": {      "invoice_id": { "type": "string", "pattern": "^INV-[0-9]{4}$" },      "currency": { "enum": ["USD", "EUR"] },      "line_items": {        "type": "array",        "minItems": 1,        "items": {          "type": "object",          "required": ["sku", "qty", "line_total"],          "properties": {            "sku": { "type": "string" },            "qty": { "type": "integer", "minimum": 1 },            "line_total": { "type": "number", "minimum": 0 }          }        }      },      "total": { "type": "number" }    }  },  "submitted_output": {    "invoice_id": "INV-7731",    "currency": "USD",    "line_items": [      { "sku": "CRWL-100", "qty": 3, "line_total": 87.0 },      { "sku": "CRWL-200", "qty": 1, "line_total": 42.5 }    ],    "total": 135.0  },  "rules": [    { "type": "sum_equals", "field": "line_items[].line_total", "equals_field": "total" }  ],  "enforce_rules": true,  "detail": "full"}

The line items sum to 129.5, but total says 135.0. With enforce_rules: true, that rule violation fails the result and comes with a fix hint:

json
{  "summary": {    "result": "fail",    "blocking_checks": ["consistency:sum_equals"]  },  "next_actions": [    { "action": "repair_and_reverify", "using": "hints" }  ],  "result": "fail",  "verification_id": "28afb453-7c39-4993-a9c4-fcade1b7924f",  "task_id": "invoice-7731-draft",  "agent_id": "test-seller-invoice-agent",  "output_hash": "d4fb804e434eb3ee047068cbb3691ea1e07066928e7e3efc73b94317e53ee305",  "schema_hash": "23ea3213715cfaf2011dabe2a9a69d4ac25b6eceec7ce3d4bfef9a1298b69b2a",  "rules_hash": "2acb6de92b88cfbca279ea6d5bd74b7a1e7dec0839dd093dbe041e25df3364d2",  "request_hash": "e4bf9733726b24a19ec546ecc79015c9b1cb7a6829b409b41ef56b1c8f60b881",  "verified_at": "2026-10-01T01:01:09.606993+00:00",  "verifier_version": "0.4.1",  "enforce_rules": true,  "strict_content_check": false,  "errors": [    "enforce_rules: consistency:sum_equals at 'line_items[].line_total': values sum to 129.5, expected total (135.0)"  ],  "errors_total": 1,  "errors_omitted": 0,  "errors_detail": [    {      "check": "consistency:sum_equals",      "path": "$.line_items[].line_total",      "expected": "a sum equal to total (135.0)",      "found": "sum 129.5",      "message": "enforce_rules: consistency:sum_equals at 'line_items[].line_total': values sum to 129.5, expected total (135.0)"    }  ],  "errors_detail_total": 1,  "errors_detail_omitted": 0,  "flags": [    {      "check": "consistency:sum_equals",      "field": "line_items[].line_total",      "severity": "error",      "detail": "values sum to 129.5, expected total (135.0)"    }  ],  "flags_total": 1,  "flags_omitted": 0,  "hints": [    {      "source": "integrity",      "check": "consistency:sum_equals",      "path": "$.line_items[].line_total",      "expected": "a sum equal to total (135.0)",      "found": "sum 129.5"    }  ],  "hints_total": 1,  "hints_omitted": 0,  "schema_compliance": { "ratio": 1.0, "passed": 22, "total": 22 },  "integrity_checks": { "ratio": 0.875, "passed": 7, "total": 8 },  "overall": { "ratio": 0.966667, "passed": 29, "total": 30 },  "verify": {    "public_key_url": "https://fastapi-service-5ag4.onrender.com/.well-known/agent-card.json",    "key_version": "v1-2026-09c",    "canonicalization": "RFC 8785 (JCS)",    "hash_algorithm": "SHA-256",    "service": "Agent Output Verifier",    "mcp": "https://fastapi-service-5ag4.onrender.com/mcp"  },  "attestation": {    "algorithm": "Ed25519",    "key_version": "v1-2026-09c",    "timestamp": "2026-10-01T01:01:09.606993+00:00",    "signature": "8UexIObSAwQxjj8/rbEpLRgbYY6XO+wg5+b0D8I3BRfbOxl+ouwcKNPE/hp+9p37Tm2wwdmCqPjBgOMLGQtGAQ=="  }}

Payment evidence: $0.02 USDC on Base, settled on-chain — 0x4cb755c71413ed5419215d2d7445c34e19be79d9f15b4046802656165b774897.

2. Corrected invoice — passes (detail: "compact")

Same schema and rule, total fixed to match the line items (129.5), requested with "detail": "compact" to get back only the summary, receipt fields and signature:

json
{  "task_id": "invoice-7731-final",  "agent_id": "test-seller-invoice-agent",  "expected_schema": { "...": "same schema as above" },  "submitted_output": {    "invoice_id": "INV-7731",    "currency": "USD",    "line_items": [      { "sku": "CRWL-100", "qty": 3, "line_total": 87.0 },      { "sku": "CRWL-200", "qty": 1, "line_total": 42.5 }    ],    "total": 129.5  },  "rules": [    { "type": "sum_equals", "field": "line_items[].line_total", "equals_field": "total" }  ],  "enforce_rules": true,  "detail": "compact"}
json
{  "summary": {    "result": "pass",    "blocking_checks": []  },  "next_actions": [    { "action": "attach_receipt", "for": "seller" },    { "action": "proceed_to_payment", "for": "buyer" }  ],  "result": "pass",  "verification_id": "96b4f722-04c3-47c7-8708-5bba97fd18b5",  "task_id": "invoice-7731-final",  "agent_id": "test-seller-invoice-agent",  "output_hash": "39e3d0a1431e3ce9cda89a1d2873e1ffb4e34f4eeded2ffa87946fbd941a34c3",  "schema_hash": "23ea3213715cfaf2011dabe2a9a69d4ac25b6eceec7ce3d4bfef9a1298b69b2a",  "rules_hash": "2acb6de92b88cfbca279ea6d5bd74b7a1e7dec0839dd093dbe041e25df3364d2",  "verified_at": "2026-10-01T01:01:15.158857+00:00",  "verifier_version": "0.4.1",  "enforce_rules": true,  "strict_content_check": false,  "verify": {    "public_key_url": "https://fastapi-service-5ag4.onrender.com/.well-known/agent-card.json",    "key_version": "v1-2026-09c",    "canonicalization": "RFC 8785 (JCS)",    "hash_algorithm": "SHA-256",    "service": "Agent Output Verifier",    "mcp": "https://fastapi-service-5ag4.onrender.com/mcp"  },  "attestation": {    "algorithm": "Ed25519",    "key_version": "v1-2026-09c",    "timestamp": "2026-10-01T01:01:15.158857+00:00",    "signature": "ri1AEl12DoZMTKBX8V5hfuD9jOWd+BLXIciqiX1JoSHJy8iDJKKSdsJmjpQUHTkbVMxDGpNwMNmc6X9zHaSVDw=="  }}

The compact shape keeps the summary, receipt fields, verify and attestation; request_hash, errors, errors_detail, flags, hints and the three scores stay in the full shape (see detail above).

Payment evidence: $0.02 USDC on Base, settled on-chain — 0xaa9161736ac410b6ac9ccc478780aa2feaa6d2cf02af4c51855e099c14499079.

Verifying these two receipts yourself

Both responses above were checked against the live agent-card's public key for v1-2026-09c before being included here, using the steps in Verifying a receipt. Confirm it yourself the same way: fetch https://fastapi-service-5ag4.onrender.com/.well-known/agent-card.json, confirm v1-2026-09c is listed, and re-run the same five steps against the two JSON blocks above — the signatures were computed once, over exactly this data, and will verify identically for anyone.

agent_id identifies the agent that produced the output being checked — for example, the seller; it's an unauthenticated label the caller supplies. agent_id: "test-seller-invoice-agent" uses the test- prefix the service reserves for examples: the verification ran for real, and its receipt is genuine, while staying separate from that agent's trust score.

License

Documentation and examples in this repository are licensed under the MIT License. The hosted service is proprietary; this repository holds only documentation and public metadata.

來源：README.md，提交 3018261

工具

0
工具後設資料尚未被收錄。

版本歷史

1
  1. v0.3.2最新Oct 1, 2026