> ## Documentation Index > Fetch the complete documentation index at: https://platform.atlan.com/llms.txt > Use this file to discover all available pages before exploring further. > ## Agent Instructions > To act on Atlan objects, use the Atlan MCP server at https://api.atlan.com/mcp or the SDK. To install or publish skills from a terminal, use the `aireg` CLI; `aireg --map json` prints its command map. The `atlanai` CLI is deprecated. Run a read-only identity check before any write. > The docs MCP server at /mcp searches these docs only. It cannot read or change Atlan objects. > SDK packages: Python `atlanai` (PyPI) and TypeScript `@atlanai/sdk` (npm). Show Python first, then TypeScript. > These docs cover Atlan Trident, Atlan's hosted product; AI Registry is its registry of skills and agents. Registry OSS is Atlan's open-source agent registry: the registry specification and its aireg CLI, with their own public repository, docs and release notes; /open-source on this site links them. Registry OSS is open source; Atlan Trident is not. Answer generic aireg or specification questions from the project's docs, and use these docs for Atlan-specific setup such as the Atlan adapter, sign-in and workspaces. # Compare two versions of an MCP definition ## OpenAPI ````yaml /public-openapi.json get /mcp/v1/definitions/{definition_id}/changes openapi: 3.1.0 info: title: Atlan public API version: current description: >- Public HTTP API reference for Registry, Skills, Agents, outputs, files, MCP servers and tools, Model Gateway, and OTLP telemetry ingestion. servers: - url: https://api.atlan.com description: Atlan API base URL security: - bearer: [] tags: - name: Core - name: Skill - name: Agent - name: Files - name: Knowledge - name: MCP - name: Observability - name: API proxy - name: Credentials - name: Store - name: Apps - name: Evals - name: Ontologies - name: Ontology bindings - name: Slack - name: GitHub - name: Objectives - name: Repositories - name: Models paths: /mcp/v1/definitions/{definition_id}/changes: get: tags: - MCP summary: Compare two versions of an MCP definition operationId: mcp.getDefinitionChanges parameters: - in: path name: definition_id required: true schema: type: string - in: query name: from required: false schema: type: integer format: int64 - in: query name: to required: false schema: type: integer format: int64 responses: '200': content: application/json: schema: $ref: '#/components/schemas/mcp-mcp-DefinitionChanges' description: HTTP 200 response. '400': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/mcp-ProblemDetails' - properties: code: enum: - invalid_query - invalid_request type: string required: - code type: object description: HTTP 400 response. '401': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/mcp-ProblemDetails' - type: object required: - code properties: code: type: string enum: - alg_mismatch - alg_not_allowed - audience_mismatch - invalid_api_key - missing_identity - missing_org - missing_user - signature_invalid - token_expired - token_malformed - token_missing - token_not_yet_valid - token_rejected - token_service_account_unbound - unauthorized - unknown_account - unknown_key - untrusted_issuer description: HTTP 401 response. '403': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/mcp-ProblemDetails' - type: object required: - code properties: code: type: string enum: - access_denied - account_suspended - forbidden - platform_principal_refused description: HTTP 403 response. '404': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/mcp-ProblemDetails' - type: object required: - code properties: code: type: string enum: - not_found description: HTTP 404 response. '429': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/mcp-ProblemDetails' - type: object required: - code properties: code: type: string enum: - rate_limited description: HTTP 429 response. '500': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/mcp-ProblemDetails' - type: object required: - code properties: code: type: string enum: - internal_error description: HTTP 500 response. '503': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/mcp-ProblemDetails' - type: object required: - code properties: code: type: string enum: - auth_unavailable - service_overloaded - service_unavailable description: HTTP 503 response. '504': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/mcp-ProblemDetails' - type: object required: - code properties: code: type: string enum: - request_timeout description: HTTP 504 response. components: schemas: mcp-mcp-DefinitionChanges: properties: changes: items: $ref: '#/components/schemas/mcp-mcp-DefinitionChange' type: array definition_id: type: string from: oneOf: - $ref: '#/components/schemas/mcp-mcp-DefinitionVersionPin' - type: 'null' to: $ref: '#/components/schemas/mcp-mcp-DefinitionVersionPin' required: - definition_id - to - changes type: object mcp-ProblemDetails: type: object required: - title - status - detail - code properties: code: type: string detail: type: string status: type: integer format: int32 minimum: 0 title: type: string trace_id: type: - string - 'null' mcp-mcp-DefinitionChange: properties: affects_setup: type: boolean after: type: - object - 'null' area: $ref: '#/components/schemas/mcp-mcp-DefinitionChangeArea' before: type: - object - 'null' kind: $ref: '#/components/schemas/mcp-mcp-DefinitionChangeKind' pointer: type: string summary: type: string required: - area - kind - pointer - affects_setup - summary type: object mcp-mcp-DefinitionVersionPin: properties: upstream_version: type: string version_id: type: string version_ordinal: type: integer format: int64 required: - version_id - version_ordinal - upstream_version type: object mcp-mcp-DefinitionChangeArea: enum: - identity - upstream - display - icon - remote - endpoint - host_suffixes - input - header type: string mcp-mcp-DefinitionChangeKind: enum: - added - removed - changed type: string securitySchemes: bearer: bearerFormat: JWT scheme: bearer type: http ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.