> ## Documentation Index > Fetch the complete documentation index at: https://docs.labelbox.com/llms.txt > Use this file to discover all available pages before exploring further. # Test an MCP server connection and list its tools > Opens a live connection to an MCP server using exactly the credential resolution a session would use, and returns the tools it advertises. A server that cannot be reached or authenticated is still HTTP 200 with ok=false, so inspect that field rather than relying on the status code. Pass vault_ids to probe authenticated; omit them to probe anonymously. ## OpenAPI ````yaml /recursion/openapi.yaml post /managed-agents/v1/mcp/probe openapi: 3.1.0 info: title: Managed Agents API version: 0.14.0 description: >- The Recursion Managed Agents REST API. Authenticate with a Recursion API key as a bearer token. An organization-scoped key acts in its own organization and needs nothing else; a tenant-scoped key must also send `x-organization-id` with an organization id or `default`. Field names follow each operation's published schema. servers: - url: https://api.recursion.labelbox.com security: - bearerAuth: [] paths: /managed-agents/v1/mcp/probe: post: tags: - Vaults summary: Test an MCP server connection and list its tools description: >- Opens a live connection to an MCP server using exactly the credential resolution a session would use, and returns the tools it advertises. A server that cannot be reached or authenticated is still HTTP 200 with ok=false, so inspect that field rather than relying on the status code. Pass vault_ids to probe authenticated; omit them to probe anonymously. operationId: managedAgentsProbeMCPServer parameters: - $ref: '#/components/parameters/RecursionTenantId' - $ref: '#/components/parameters/RecursionOrganizationId' requestBody: content: application/json: schema: $ref: '#/components/schemas/ProbeMCPServerRequest' required: true responses: '200': content: application/json: schema: $ref: '#/components/schemas/MCPProbeResponse' description: >- Response body of POST /managed-agents/v1/mcp/probe: the result of one live connection attempt to an MCP server, run through the same URL and vault resolution a real session uses. This envelope is a verdict rather than a resource: a server that is down is still HTTP 200 with ok=false, so a caller can distinguish "the server you configured is unreachable" from "this API is unreachable". Nothing is persisted by a probe. headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '400': description: Bad Request. content: application/json: schema: oneOf: - $ref: '#/components/schemas/ManagedAgentsApiErrorInvalidJson' - $ref: '#/components/schemas/ManagedAgentsApiErrorInvalidRequest' discriminator: propertyName: code mapping: invalid_json: '#/components/schemas/ManagedAgentsApiErrorInvalidJson' invalid_request: '#/components/schemas/ManagedAgentsApiErrorInvalidRequest' x-recursion-error-codes: - invalid_json - invalid_request headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '401': description: Unauthorized. content: application/json: schema: $ref: '#/components/schemas/ManagedAgentsApiErrorUnauthorized' x-recursion-error-codes: - unauthorized headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '403': description: Forbidden. content: application/json: schema: $ref: '#/components/schemas/ManagedAgentsApiErrorForbidden' x-recursion-error-codes: - forbidden headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '404': description: Not Found. content: application/json: schema: $ref: '#/components/schemas/ManagedAgentsApiErrorNotFound' x-recursion-error-codes: - not_found headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '413': description: Payload Too Large. content: application/json: schema: $ref: '#/components/schemas/ManagedAgentsApiErrorPayloadTooLarge' x-recursion-error-codes: - payload_too_large headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '415': description: Unsupported Media Type. content: application/json: schema: $ref: '#/components/schemas/ManagedAgentsApiErrorUnsupportedMediaType' x-recursion-error-codes: - unsupported_media_type headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '429': headers: Retry-After: description: When to retry, as delay seconds or an HTTP date. schema: type: string recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' description: Too Many Requests. content: application/json: schema: $ref: '#/components/schemas/ManagedAgentsApiErrorRateLimitExceeded' x-recursion-error-codes: - rate_limit_exceeded '500': description: Internal Server Error. content: application/json: schema: $ref: '#/components/schemas/ManagedAgentsApiErrorInternalError' x-recursion-error-codes: - internal_error headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '502': description: A dependent service returned an invalid response. content: application/json: schema: $ref: '#/components/schemas/ManagedAgentsApiErrorDependencyFailure' x-recursion-error-codes: - bad_gateway headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '503': description: Service Unavailable. content: application/json: schema: oneOf: - $ref: >- #/components/schemas/ManagedAgentsApiErrorCredentialEncryptionUnconfigured - $ref: >- #/components/schemas/ManagedAgentsApiErrorManagedAgentsUnavailable - $ref: >- #/components/schemas/ManagedAgentsApiErrorServiceUnavailable discriminator: propertyName: code mapping: credential_encryption_unconfigured: >- #/components/schemas/ManagedAgentsApiErrorCredentialEncryptionUnconfigured managed_agents_unavailable: >- #/components/schemas/ManagedAgentsApiErrorManagedAgentsUnavailable service_unavailable: >- #/components/schemas/ManagedAgentsApiErrorServiceUnavailable x-recursion-error-codes: - credential_encryption_unconfigured - managed_agents_unavailable - service_unavailable headers: recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' '504': headers: Retry-After: description: When to retry, as delay seconds or an HTTP date. schema: type: string recursion-organization-id: $ref: '#/components/headers/RecursionOrganizationId' recursion-tenant-id: $ref: '#/components/headers/RecursionTenantId' description: A dependent service timed out. content: application/json: schema: $ref: '#/components/schemas/ManagedAgentsApiErrorDependencyTimeout' x-recursion-error-codes: - gateway_timeout components: parameters: RecursionTenantId: name: x-tenant-id in: header required: false description: >- Optional tenant consistency check. When present, it must name the tenant bound to the API key, including when x-organization-id is `default`. schema: type: string minLength: 1 RecursionOrganizationId: name: x-organization-id in: header required: false description: >- Organization in which to act. Required for a tenant-scoped API key. Optional for an organization-scoped key, where it must name that same organization. The value may be an organization id or `default`. schema: type: string minLength: 1 schemas: ProbeMCPServerRequest: description: >- Request body for a live connection test against an MCP server, running the same credential resolution a session would. An unreachable server is reported in the response body, not as an HTTP error. properties: server_url: description: >- The MCP server to connect to. Must be http or https and must not embed credentials. type: string vault_ids: description: >- Vaults whose credentials may be used, scoped exactly as a session's grant is. Omit to probe unauthenticated. items: type: string type: array required: - server_url type: object additionalProperties: false MCPProbeResponse: description: >- Response body of POST /managed-agents/v1/mcp/probe: the result of one live connection attempt to an MCP server, run through the same URL and vault resolution a real session uses. This envelope is a verdict rather than a resource: a server that is down is still HTTP 200 with ok=false, so a caller can distinguish "the server you configured is unreachable" from "this API is unreachable". Nothing is persisted by a probe. properties: credential_matched: description: >- True when a credential from the named vaults was opened and attached to the request. It reports whether this attempt was authenticated, not whether a credential exists: a credential that matched the server URL but could not be opened reports false and sets credential_unopenable, because nothing was sent. type: boolean credential_unopenable: description: >- Set when a credential matched this server URL and could not be opened, so the request carried no auth header. external_reference means the material is held outside this service and must be re-entered here; material_missing means the credential row carries no stored value. Empty when none matched or the match was usable. enum: - external_reference - material_missing type: string deployment_authorized: description: >- Deprecated. Always false: deployment-wide hosted MCP reader policies are disabled. Use a vault credential or organization-scoped integration grant for authenticated tool calls. type: boolean error: description: >- Operator-facing diagnostic when the probe failed. Never contains credential material. type: string fault: description: >- Set when the server was never reached for a reason other than the network, with reachable=false. egress_blocked means the server URL resolves to a private, loopback, link-local, or metadata address, which this service refuses to connect to; use a public URL. token_invalid means the stored token contains a line break, so it cannot be sent as a header; save it again without it. Empty for every other outcome, including genuine network failures. enum: - egress_blocked - token_invalid type: string ok: description: >- True when the server completed the handshake and returned a tool list. type: boolean protocol_version: description: The MCP protocol version used. type: string reachable: description: >- True when the server answered. Either the handshake succeeded (protocol_version is set), even if listing tools then failed, or the server refused the credential or its absence with HTTP 401 or 403 (protocol_version is absent): the URL and network are fine, and the credential is what to fix. type: boolean server_name: description: >- What the server called itself during the handshake, which is how an operator confirms the URL reached the intended service. type: string tools: description: >- Tools the server advertised on this attempt. Always an array and never null: empty means the handshake succeeded but the server offered no tools, or listing them failed, which is what ok=false plus reachable=true reports. items: $ref: '#/components/schemas/MCPProbeTool' type: array required: - ok - reachable - credential_matched - deployment_authorized - tools type: object additionalProperties: false ManagedAgentsApiErrorInvalidJson: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - invalid_json message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorInvalidRequest: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - invalid_request message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorUnauthorized: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - unauthorized message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorForbidden: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - forbidden message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorNotFound: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - not_found message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorPayloadTooLarge: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - payload_too_large message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorUnsupportedMediaType: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - unsupported_media_type message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorRateLimitExceeded: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - rate_limit_exceeded message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorInternalError: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - internal_error message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorDependencyFailure: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - bad_gateway message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorCredentialEncryptionUnconfigured: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - credential_encryption_unconfigured message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorManagedAgentsUnavailable: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - managed_agents_unavailable message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorServiceUnavailable: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - service_unavailable message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. ManagedAgentsApiErrorDependencyTimeout: type: object properties: code: type: string minLength: 1 description: Stable machine-readable error code. enum: - gateway_timeout message: type: string minLength: 1 description: Human-readable error message. details: $ref: '#/components/schemas/ManagedAgentsApiErrorDetails' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. required: - code - message additionalProperties: false description: Standard flat error response. MCPProbeTool: description: >- One tool advertised by a probed MCP server, reported verbatim from its tools/list response. Appears only inside MCPProbeResponse.tools; the service does not persist or validate these entries, so their presence proves the server answered, not that the tool works. properties: description: description: >- The tool's own self-description as returned by the server, passed through verbatim. Absent when the server advertised the tool without one. type: string name: description: >- The tool name as the MCP server reported it, which is the name an agent would call it by. type: string required: - name type: object additionalProperties: false ManagedAgentsApiErrorDetails: type: object properties: field: description: >- Request field or header responsible for the error, when one can be identified. type: string issues: description: >- Boundary-validation failures as path-prefixed human-readable messages. type: array items: type: string requestId: description: Request correlation identifier for support and log lookup. type: string retryable: description: >- Server advice about failure transience. `true` means transient, `false` means non-transient, and absence gives no advice. Automatic replay is allowed only when this field is not `false` and the operation-specific retry and idempotency contract permits replay. type: boolean additionalProperties: $ref: '#/components/schemas/PlatformSafeJsonValue' description: >- Optional structured error details. Reserved transport fields are typed; code-specific fields remain forward compatible. PlatformSafeJsonValue: description: >- A JSON value whose integer members stay within the exact ECMAScript safe-integer range at every nesting level. oneOf: - type: 'null' - type: boolean - type: string - type: integer minimum: -9007199254740991 maximum: 9007199254740991 - type: number not: type: integer - type: array items: $ref: '#/components/schemas/PlatformSafeJsonValue' - additionalProperties: $ref: '#/components/schemas/PlatformSafeJsonValue' type: object headers: RecursionOrganizationId: description: Organization id resolved for this request. schema: type: string minLength: 1 RecursionTenantId: description: Tenant id resolved for this request. schema: type: string minLength: 1 securitySchemes: bearerAuth: type: http scheme: bearer description: A Recursion API key, created in the console under API keys. ````