Agent Verification Utility MCP
Provides deterministic JSON verification tools for AI agents, allowing checks on field presence, expected values, types, and SHA-256 digests. It supports free pre-checks and paid execution via x402 protocol on Base, returning Ed25519-signed evidence for verified assertions.
Endpoint and access
No sign-in to connect and list tools. Individual tools may still need a vendor account, credentials, or permissions; check the documented prerequisites.
https://agent-economy.kgninja.dev/mcpWhat its tools do
5 tools, grouped by the hints the server advertises. Hints are self-declared, not verified behavior.
Read-only (2)
Can change data (3)
Checks and signals
Each line is separate evidence, not a trust score.
- Passed Endpoint answered the live check ·
- Passed Official MCP Registry namespace is tied to agent-economy.kgninja.dev ·
- Passed Endpoint is on the registry namespace domain ·
- Availability 1 of 1 checks passed in 30 days
What you can do with it
- Check explicit JSON conditions before agent steps
- Verify field presence and expected values in JSON
- Execute paid assertions with Ed25519-signed evidence
- Validate payment eligibility and spend policies
Source and maintenance
Protocol and capabilities
- Server
- dev.kgninja/agent-verification-utility 0.4.3
- MCP protocol negotiated in check
- 2025-11-25
- Tools
- 5 advertised
- Resources
- Not advertised
- Resource templates
- Not advertised
- Prompts
- Not advertised
{
"tools": {
"listChanged": true
}
}Tools
5 advertised
describe_verify_evidence — Describe Agent Verification Utility
Describe when deterministic verification is useful, when it is not, free request validation, recipes, limits, and the explicit paid MCP path.
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {}
}{
"readOnlyHint": true,
"openWorldHint": false,
"idempotentHint": true,
"destructiveHint": false
}get_revenue_goal_status — Get Revenue Goal Status
Read the active revenue goal, measured funnel, contribution margin, and the next bounded improvement recommendation. This tool never changes price, spends funds, or sends messages.
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {}
}{
"readOnlyHint": true,
"openWorldHint": false,
"idempotentHint": true,
"destructiveHint": false
}quote_verify_evidence — Quote Verification
Obtain a free bound quote for deterministic checks on supplied JSON before deciding to purchase. After a successful free precheck at POST /validate-request, supply the unchanged intent and its precheck_receipt.receipt_digest. Creates or reuses a persisted quote and records observability events; no payment, signing or paid verification is performed. The bound quote ties request/evidence digests, precheck digest, spend policy, quoted amount, network, asset, recipient and expiry together. Server availability, fresh cost basis and conservative contribution-margin thresholds must pass. Returns the quote as JSON text and structuredContent: quote_id, request_hash, price (atomic USDC, 6 decimals), expires_at, economic_guard, purchase instructions and paid_verification_binding in state quoted, not a paid receipt. Application failures return isError=true with JSON error.code, message, retryable and optional details (for example PRECHECK_STALE, PRICE_CAP_EXCEEDED, IDEMPOTENCY_KEY_CONFLICT, IDEMPOTENCY_KEY_EXPIRED or UNPROFITABLE_TRANSACTION); invalid argument shapes are rejected by MCP schema validation. Re-run precheck after request/policy changes; do not pay on refusal. Next use prepare_verify_evidence_purchase with the same key and intent for the HTTP purchase request, or explicitly authorize the separate paid verify_evidence flow.
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"idempotency_key",
"intent"
],
"properties": {
"intent": {
"type": "object",
"required": [
"request",
"spend_policy",
"precheck_receipt_digest"
],
"properties": {
"request": {
"type": "object",
"required": [
"client_request_id",
"evidence",
"assertions"
],
"properties": {
"evidence": {
"type": "object",
"required": [
"media_type",
"content_base64"
],
"properties": {
"media_type": {
"type": "string",
"const": "application/json",
"description": "Required literal application/json."
},
"content_base64": {
"type": "string",
"maxLength": 87384,
"minLength": 4,
"description": "Required strict standard Base64 of UTF-8 JSON; 4-87384 encoded characters and at most 65536 decoded bytes. JSON limits: depth 32, object keys 2048, values 8192; integers must be JavaScript safe integers."
}
},
"description": "Required caller-supplied JSON bytes; no remote evidence is fetched.",
"additionalProperties": false
},
"assertions": {
"type": "array",
"items": {
"oneOf": [
{
"type": "object",
"required": [
"op",
"expected_hex"
],
"properties": {
"op": {
"type": "string",
"const": "sha256_equals",
"description": "Compare SHA-256 of the raw decoded evidence bytes."
},
"expected_hex": {
"type": "string",
"pattern": "^[a-f0-9]{64}$",
"description": "Required expected digest as exactly 64 lowercase hex characters, without sha256: prefix."
}
},
"additionalProperties": false
},
{
"type": "object",
"required": [
"op",
"path"
],
"properties": {
"op": {
"type": "string",
"const": "json_pointer_exists",
"description": "Check whether the JSON Pointer resolves."
},
"path": {
"type": "string",
"maxLength": 512,
"description": "Required RFC 6901 JSON Pointer, at most 512 characters; empty string selects the document root. Escape tilde as ~0 and slash as ~1."
}
},
"additionalProperties": false
},
{
"type": "object",
"required": [
"op",
"path",
"expected"
],
"properties": {
"op": {
"type": "string",
"const": "json_pointer_equals",
"description": "Compare the selected JSON value with expected."
},
"path": {
"type": "string",
"maxLength": 512,
"description": "Required RFC 6901 JSON Pointer, at most 512 characters; empty string selects the document root. Escape tilde as ~0 and slash as ~1."
},
"expected": {
"description": "Required expected JSON value, including null; JSON depth/key/value and safe-integer limits apply."
}
},
"additionalProperties": false
},
{
"type": "object",
"required": [
"op",
"path",
"expected_type"
],
"properties": {
"op": {
"type": "string",
"const": "json_type_is",
"description": "Check the selected JSON value type."
},
"path": {
"type": "string",
"maxLength": 512,
"description": "Required RFC 6901 JSON Pointer, at most 512 characters; empty string selects the document root. Escape tilde as ~0 and slash as ~1."
},
"expected_type": {
"enum": [
"null",
"boolean",
"number",
"string",
"array",
"object"
],
"type": "string",
"description": "Required JSON type: null, boolean, number, string, array or object."
}
},
"additionalProperties": false
}
]
},
"maxItems": 16,
"minItems": 1,
"description": "Required 1-16 deterministic assertions. Each operation accepts only its documented fields. Precheck validates input, not assertion truth."
},
"client_request_id": {
"type": "string",
"pattern": "^[A-Za-z0-9._:-]+$",
"maxLength": 64,
"minLength": 1,
"description": "Required caller request identifier, 1-64 characters from A-Z, a-z, 0-9, dot, underscore, colon or hyphen; included in the request hash."
}
},
"description": "Required complete bounded verification request, unchanged from precheck; no optional fields or defaults.",
"additionalProperties": false
},
"spend_policy": {
"type": "object",
"required": [
"policy_version",
"max_amount_atomic",
"network",
"asset",
"pay_to"
],
"properties": {
"asset": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "Required USDC contract address, 0x plus 40 hex characters; must match current advertised asset."
},
"pay_to": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "Required allowed payment recipient, 0x plus 40 hex characters; must match current advertised payTo."
},
"network": {
"enum": [
"eip155:84532",
"eip155:8453"
],
"type": "string",
"description": "Required eip155:8453 (Base) or eip155:84532 (Base Sepolia); must match current advertised terms."
},
"policy_version": {
"type": "string",
"const": "agent-economy/precheck-policy/2.0",
"description": "Required literal agent-economy/precheck-policy/2.0."
},
"max_amount_atomic": {
"type": "string",
"description": "Required positive decimal integer string in atomic USDC units (1000000 = 1 USDC), at most 16 digits and within JavaScript safe-integer range. No leading zero; must cover the current quoted price."
}
},
"description": "Required caller spending limits and allowed terms; preserve from precheck. All five fields required; no defaults.",
"additionalProperties": false
},
"precheck_receipt_digest": {
"type": "string",
"pattern": "^sha256:[a-f0-9]{64}$",
"description": "Required sha256: followed by 64 lowercase hex characters, copied from precheck_receipt.receipt_digest of the successful free precheck. Recomputed against request, policy and current discovery contract; mismatches return PRECHECK_STALE."
}
},
"description": "Required prechecked purchase intent: request, spend_policy and precheck_receipt_digest are all required, with no defaults or optional fields. Preserve the request and policy used in the successful free POST /validate-request.",
"additionalProperties": false
},
"idempotency_key": {
"type": "string",
"pattern": "^[A-Za-z0-9_-]+$",
"maxLength": 128,
"minLength": 16,
"description": "Required 16-128 characters from A-Z, a-z, 0-9, underscore or hyphen. Reuse with the unchanged intent to reuse an unexpired quote; changed bindings return IDEMPOTENCY_KEY_CONFLICT. An expired key returns IDEMPOTENCY_KEY_EXPIRED; use a new key."
}
}
}{
"readOnlyHint": false,
"openWorldHint": false,
"idempotentHint": true,
"destructiveHint": false
}prepare_verify_evidence_purchase — Prepare HTTP Purchase
Prepare an HTTP purchase request for deterministic JSON verification after a successful free precheck; a prior quote tool call is optional. After a successful free precheck at POST /validate-request, supply the unchanged intent and its precheck_receipt.receipt_digest. Creates or reuses a persisted quote and records observability events; no payment, signing or paid verification is performed. The bound quote ties request/evidence digests, precheck digest, spend policy, quoted amount, network, asset, recipient and expiry together. Server availability, fresh cost basis and conservative contribution-margin thresholds must pass. Returns JSON text and structuredContent containing quote, request (POST /verify-evidence, content-type and X-Quote-ID headers, unchanged intent body), expected_first_status=402 and expected_payment_header=PAYMENT-REQUIRED. It does not send this request. Application failures return isError=true with JSON error.code, message, retryable and optional details (for example PRECHECK_STALE, PRICE_CAP_EXCEEDED, IDEMPOTENCY_KEY_CONFLICT, IDEMPOTENCY_KEY_EXPIRED or UNPROFITABLE_TRANSACTION); invalid argument shapes are rejected by MCP schema validation. Re-run precheck after request/policy changes; do not pay on refusal. Next send the returned request to obtain a challenge, check binding, amount, network, asset, payTo and expiry against local policy, then authorize payment separately. Use quote_verify_evidence when only quote terms are needed.
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"idempotency_key",
"intent"
],
"properties": {
"intent": {
"type": "object",
"required": [
"request",
"spend_policy",
"precheck_receipt_digest"
],
"properties": {
"request": {
"type": "object",
"required": [
"client_request_id",
"evidence",
"assertions"
],
"properties": {
"evidence": {
"type": "object",
"required": [
"media_type",
"content_base64"
],
"properties": {
"media_type": {
"type": "string",
"const": "application/json",
"description": "Required literal application/json."
},
"content_base64": {
"type": "string",
"maxLength": 87384,
"minLength": 4,
"description": "Required strict standard Base64 of UTF-8 JSON; 4-87384 encoded characters and at most 65536 decoded bytes. JSON limits: depth 32, object keys 2048, values 8192; integers must be JavaScript safe integers."
}
},
"description": "Required caller-supplied JSON bytes; no remote evidence is fetched.",
"additionalProperties": false
},
"assertions": {
"type": "array",
"items": {
"oneOf": [
{
"type": "object",
"required": [
"op",
"expected_hex"
],
"properties": {
"op": {
"type": "string",
"const": "sha256_equals",
"description": "Compare SHA-256 of the raw decoded evidence bytes."
},
"expected_hex": {
"type": "string",
"pattern": "^[a-f0-9]{64}$",
"description": "Required expected digest as exactly 64 lowercase hex characters, without sha256: prefix."
}
},
"additionalProperties": false
},
{
"type": "object",
"required": [
"op",
"path"
],
"properties": {
"op": {
"type": "string",
"const": "json_pointer_exists",
"description": "Check whether the JSON Pointer resolves."
},
"path": {
"type": "string",
"maxLength": 512,
"description": "Required RFC 6901 JSON Pointer, at most 512 characters; empty string selects the document root. Escape tilde as ~0 and slash as ~1."
}
},
"additionalProperties": false
},
{
"type": "object",
"required": [
"op",
"path",
"expected"
],
"properties": {
"op": {
"type": "string",
"const": "json_pointer_equals",
"description": "Compare the selected JSON value with expected."
},
"path": {
"type": "string",
"maxLength": 512,
"description": "Required RFC 6901 JSON Pointer, at most 512 characters; empty string selects the document root. Escape tilde as ~0 and slash as ~1."
},
"expected": {
"description": "Required expected JSON value, including null; JSON depth/key/value and safe-integer limits apply."
}
},
"additionalProperties": false
},
{
"type": "object",
"required": [
"op",
"path",
"expected_type"
],
"properties": {
"op": {
"type": "string",
"const": "json_type_is",
"description": "Check the selected JSON value type."
},
"path": {
"type": "string",
"maxLength": 512,
"description": "Required RFC 6901 JSON Pointer, at most 512 characters; empty string selects the document root. Escape tilde as ~0 and slash as ~1."
},
"expected_type": {
"enum": [
"null",
"boolean",
"number",
"string",
"array",
"object"
],
"type": "string",
"description": "Required JSON type: null, boolean, number, string, array or object."
}
},
"additionalProperties": false
}
]
},
"maxItems": 16,
"minItems": 1,
"description": "Required 1-16 deterministic assertions. Each operation accepts only its documented fields. Precheck validates input, not assertion truth."
},
"client_request_id": {
"type": "string",
"pattern": "^[A-Za-z0-9._:-]+$",
"maxLength": 64,
"minLength": 1,
"description": "Required caller request identifier, 1-64 characters from A-Z, a-z, 0-9, dot, underscore, colon or hyphen; included in the request hash."
}
},
"description": "Required complete bounded verification request, unchanged from precheck; no optional fields or defaults.",
"additionalProperties": false
},
"spend_policy": {
"type": "object",
"required": [
"policy_version",
"max_amount_atomic",
"network",
"asset",
"pay_to"
],
"properties": {
"asset": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "Required USDC contract address, 0x plus 40 hex characters; must match current advertised asset."
},
"pay_to": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "Required allowed payment recipient, 0x plus 40 hex characters; must match current advertised payTo."
},
"network": {
"enum": [
"eip155:84532",
"eip155:8453"
],
"type": "string",
"description": "Required eip155:8453 (Base) or eip155:84532 (Base Sepolia); must match current advertised terms."
},
"policy_version": {
"type": "string",
"const": "agent-economy/precheck-policy/2.0",
"description": "Required literal agent-economy/precheck-policy/2.0."
},
"max_amount_atomic": {
"type": "string",
"description": "Required positive decimal integer string in atomic USDC units (1000000 = 1 USDC), at most 16 digits and within JavaScript safe-integer range. No leading zero; must cover the current quoted price."
}
},
"description": "Required caller spending limits and allowed terms; preserve from precheck. All five fields required; no defaults.",
"additionalProperties": false
},
"precheck_receipt_digest": {
"type": "string",
"pattern": "^sha256:[a-f0-9]{64}$",
"description": "Required sha256: followed by 64 lowercase hex characters, copied from precheck_receipt.receipt_digest of the successful free precheck. Recomputed against request, policy and current discovery contract; mismatches return PRECHECK_STALE."
}
},
"description": "Required prechecked purchase intent: request, spend_policy and precheck_receipt_digest are all required, with no defaults or optional fields. Preserve the request and policy used in the successful free POST /validate-request.",
"additionalProperties": false
},
"idempotency_key": {
"type": "string",
"pattern": "^[A-Za-z0-9_-]+$",
"maxLength": 128,
"minLength": 16,
"description": "Required 16-128 characters from A-Z, a-z, 0-9, underscore or hyphen. Reuse with the unchanged intent to reuse an unexpired quote; changed bindings return IDEMPOTENCY_KEY_CONFLICT. An expired key returns IDEMPOTENCY_KEY_EXPIRED; use a new key."
}
}
}{
"readOnlyHint": false,
"openWorldHint": false,
"idempotentHint": true,
"destructiveHint": false
}verify_evidence — Verify Evidence (paid)
Run deterministic checks and return Ed25519-signed evidence after one explicitly authorized x402 payment. A free precheck receipt and a matching bound payment requirement are required before signing.
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"idempotency_key",
"intent"
],
"properties": {
"intent": {
"type": "object",
"required": [
"request",
"spend_policy",
"precheck_receipt_digest"
],
"properties": {
"request": {
"type": "object",
"required": [
"client_request_id",
"evidence",
"assertions"
],
"properties": {
"evidence": {
"type": "object",
"required": [
"media_type",
"content_base64"
],
"properties": {
"media_type": {
"type": "string",
"const": "application/json"
},
"content_base64": {
"type": "string",
"maxLength": 87384,
"minLength": 4
}
},
"additionalProperties": false
},
"assertions": {
"type": "array",
"items": {
"oneOf": [
{
"type": "object",
"required": [
"op",
"expected_hex"
],
"properties": {
"op": {
"type": "string",
"const": "sha256_equals"
},
"expected_hex": {
"type": "string",
"pattern": "^[a-f0-9]{64}$"
}
},
"additionalProperties": false
},
{
"type": "object",
"required": [
"op",
"path"
],
"properties": {
"op": {
"type": "string",
"const": "json_pointer_exists"
},
"path": {
"type": "string",
"maxLength": 512
}
},
"additionalProperties": false
},
{
"type": "object",
"required": [
"op",
"path",
"expected"
],
"properties": {
"op": {
"type": "string",
"const": "json_pointer_equals"
},
"path": {
"type": "string",
"maxLength": 512
},
"expected": {}
},
"additionalProperties": false
},
{
"type": "object",
"required": [
"op",
"path",
"expected_type"
],
"properties": {
"op": {
"type": "string",
"const": "json_type_is"
},
"path": {
"type": "string",
"maxLength": 512
},
"expected_type": {
"enum": [
"null",
"boolean",
"number",
"string",
"array",
"object"
],
"type": "string"
}
},
"additionalProperties": false
}
]
},
"maxItems": 16,
"minItems": 1
},
"client_request_id": {
"type": "string",
"pattern": "^[A-Za-z0-9._:-]+$",
"maxLength": 64,
"minLength": 1
}
},
"additionalProperties": false
},
"spend_policy": {
"type": "object",
"required": [
"policy_version",
"max_amount_atomic",
"network",
"asset",
"pay_to"
],
"properties": {
"asset": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$"
},
"pay_to": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$"
},
"network": {
"enum": [
"eip155:84532",
"eip155:8453"
],
"type": "string"
},
"policy_version": {
"type": "string",
"const": "agent-economy/precheck-policy/2.0"
},
"max_amount_atomic": {
"type": "string"
}
},
"additionalProperties": false
},
"precheck_receipt_digest": {
"type": "string",
"pattern": "^sha256:[a-f0-9]{64}$"
}
},
"additionalProperties": false
},
"idempotency_key": {
"type": "string",
"pattern": "^[A-Za-z0-9_-]+$",
"maxLength": 128,
"minLength": 16
}
}
}{
"readOnlyHint": false,
"openWorldHint": true,
"idempotentHint": true,
"destructiveHint": false
}Prompts
Not advertised
Resources
Not advertised
90-day uptime
A lightweight connection check about every six hours, sampled on hosts with many listings. It shows the server answered, not that its tools work.
- 2026-11-07: 1 of 1 checks answered
30-day availability
Aggregated from read-only remote checks; this is not a tool-execution or security guarantee.
- Successful checks
- 1 of 1 (100%)
- Average latency
- 717 ms
- 95th percentile latency
- 717 ms
Maintenance history
Public check and source-refresh events. Editorial and ownership records remain private.
- · probe · passed · 717 ms · metadata changed · 5 tool(s)
Connect from your client
Each snippet registers the same endpoint; pick the client you use.
Claude Code
claude mcp add --transport http agent-verification-utility-mcp https://agent-economy.kgninja.dev/mcpCodex
codex mcp add agent-verification-utility-mcp --url https://agent-economy.kgninja.dev/mcpCursor
{
"mcpServers": {
"agent-verification-utility-mcp": {
"url": "https://agent-economy.kgninja.dev/mcp"
}
}
}Cline
{
"mcpServers": {
"agent-verification-utility-mcp": {
"type": "streamableHttp",
"url": "https://agent-economy.kgninja.dev/mcp",
"disabled": false
}
}
}VS Code
{
"servers": {
"agent-verification-utility-mcp": {
"type": "http",
"url": "https://agent-economy.kgninja.dev/mcp"
}
}
}Gemini CLI
gemini mcp add --transport http agent-verification-utility-mcp https://agent-economy.kgninja.dev/mcpClaude Desktop
https://agent-economy.kgninja.dev/mcpWindsurf
{
"mcpServers": {
"agent-verification-utility-mcp": {
"serverUrl": "https://agent-economy.kgninja.dev/mcp"
}
}
}Let your agent find its tools
Find servers like Agent Verification Utility MCP from your agent. Add Koskamo once to search the index for endpoints, access requirements, and client setup. Public discovery needs no key.
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Do you run Agent Verification Utility MCP?
Prove ownership with a DNS record, a well-known file, or your Official MCP Registry entry, and your edits publish immediately. Proofs are re-checked weekly; admins can still hide or remove a listing.