# M-Files gRPC API

HTML version: https://developer.m-files.com/APIs/gRPC-API/

The M-Files Server gRPC API is the complete interface to M-Files Server. The M-Files web and desktop clients and M-Files Admin use it for everything they do with the server: working with objects, files and metadata, searching, workflows, and administering vaults and the server.

The [COM API](https://developer.m-files.com/APIs/COM-API/) and the [REST API](https://developer.m-files.com/APIs/REST-API/), also documented on this portal, are layers on top of the same server interface: the COM API calls it, and the REST API is built on the COM API. They expose much, but not all, of what the gRPC API offers.

* **Native gRPC (recommended).** Call the API over HTTP/2 with any gRPC implementation, using the `.proto` files below. Use it from servers, desktop applications, scripts and agents.
* **mf-http-grpc.** For browsers and other environments that cannot speak HTTP/2 gRPC, the mf-http-grpc gateway accepts the same messages over HTTP, at routes such as `POST /grpc/v1/get-object-types` (the method name in kebab case; each method page shows its route).

The API evolves with M-Files Server: most changes are additions, and methods can also be deprecated or removed. See [Versions and compatibility](https://developer.m-files.com/APIs/gRPC-API/runtime/versioning/index.md).

- **API version:** 26.11
- **Package:** `MFiles`
- **Services:** 78
- **Methods:** 712
- **Generated:** 2026-11-01T22:51:12+00:00

<a id="agents"></a>

## For coding agents

- [llms.txt](https://developer.m-files.com/APIs/gRPC-API/llms.txt): the map of this documentation, with Markdown links
- [methods.txt](https://developer.m-files.com/APIs/gRPC-API/methods.txt): one line per method
- [methods.jsonl](https://developer.m-files.com/APIs/gRPC-API/methods.jsonl): one JSON object per method
- [llms-full-vault.txt](https://developer.m-files.com/APIs/gRPC-API/llms-full-vault.txt): all pages of the Vault API as one Markdown file
- [llms-full-admin.txt](https://developer.m-files.com/APIs/gRPC-API/llms-full-admin.txt): all pages of the Administration API as one Markdown file
- [llms-full-integration.txt](https://developer.m-files.com/APIs/gRPC-API/llms-full-integration.txt): all pages of the Server integration API as one Markdown file
- [llms-full-guides.txt](https://developer.m-files.com/APIs/gRPC-API/llms-full-guides.txt): all concept, runtime and guide pages as one Markdown file

Every page has a Markdown twin: add index.md to its URL.

<a id="start-here"></a>

## Start here

- [Python quickstart](https://developer.m-files.com/APIs/gRPC-API/guides/quickstart-python/index.md): From an empty folder to a Python program that logs in to an M-Files vault over gRPC and lists its 10 most recently modified documents, on M-Files Cloud or on-premises.
- [C# quickstart](https://developer.m-files.com/APIs/gRPC-API/guides/quickstart-csharp/index.md): From nothing to a .NET console app that logs in to an M-Files vault over gRPC and lists the 10 most recently modified documents, on M-Files Cloud or on-premises.
- [Go quickstart](https://developer.m-files.com/APIs/gRPC-API/guides/quickstart-go/index.md): From nothing to a Go program that logs in to an M-Files vault over gRPC and lists the 10 most recently modified documents, on M-Files Cloud or on-premises.
- [Connecting to the server](https://developer.m-files.com/APIs/gRPC-API/runtime/connecting/index.md): Endpoints, TLS, HTTP/2, message size and keepalive limits, method paths, and a first anonymous call to check that the server answers.
- [Cloud and on-premises](https://developer.m-files.com/APIs/gRPC-API/runtime/deployments/index.md): What differs between M-Files Cloud and an on-premises M-Files Server for a gRPC caller - address, TLS, authentication and the front end.
- [Authentication and sessions](https://developer.m-files.com/APIs/gRPC-API/runtime/authentication/index.md): How to log in with each AuthDataType, bind the session to a vault, send the 48-byte session ID, keep the session alive with KeepAlive and close it with LogOut.

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## Concepts

- [Vault and metadata structure](https://developer.m-files.com/APIs/gRPC-API/concepts/vault-and-metadata-structure/index.md): How an M-Files vault is organized (object types, value lists, classes, property definitions, workflows) and the separate ID spaces that identify them.
- [Objects and versions](https://developer.m-files.com/APIs/gRPC-API/concepts/objects-and-versions/index.md): Object and version identity (ObjID, ObjVer), latest versus specific versions, check-out and check-in, files, deleted versus destroyed objects, GUIDs and external IDs.
- [Properties and values](https://developer.m-files.com/APIs/gRPC-API/concepts/properties-and-values/index.md): How property values are represented (PropertyValue, TypedValue), how to set each data type including lookups and empty values, and the rules the server enforces.
- [Search](https://developer.m-files.com/APIs/gRPC-API/concepts/search/index.md): The search condition model (expression, condition type, value), the conditions you need most with their exact message shapes, and how results, limits, sorting and paging behave.
- [Workflows](https://developer.m-files.com/APIs/gRPC-API/concepts/workflows/index.md): Workflows, states and state transitions as metadata; how to read the allowed transitions, change an object's state, and what electronic signatures add.
- [Permissions](https://developer.m-files.com/APIs/gRPC-API/concepts/permissions/index.md): Vault-level rights, object ACLs and named ACLs, effective permissions, setting the ACL of a new object, and what "access denied" looks like to a gRPC caller.
- [Metadata structure version and caching](https://developer.m-files.com/APIs/gRPC-API/concepts/metadata-structure-version-and-caching/index.md): The vault's metadata structure version (mfiles-metadata-version-bin trailer, GetMetadataStructureVersion), the per-list version numbers, and how to cache the metadata structure safely.

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## Runtime conventions

- [Call metadata](https://developer.m-files.com/APIs/gRPC-API/runtime/call-metadata/index.md): Every metadata key the server reads or writes - session ID, activity ID, remote-call marker, metadata structure version trailer, cookies - plus deadlines and call importance.
- [Errors](https://developer.m-files.com/APIs/gRPC-API/runtime/errors/index.md): How MFServer reports errors over gRPC - status codes, the error trailers, decoding the M-Files error stack, and the common error codes with what to do about each.
- [Files](https://developer.m-files.com/APIs/gRPC-API/runtime/files/index.md): How to download and upload file content - download sessions, block sizes, upload sessions and inline content, which method to choose, and the limits that apply.
- [Versions and compatibility](https://developer.m-files.com/APIs/gRPC-API/runtime/versioning/index.md): How the API changes between versions, how to find out what a server supports (QueryVersion, GetServerCapabilities), what to send in ClientData, and the compatibility rules that let one client work with older and newer servers.
- [HTTP access (mf-http-grpc)](https://developer.m-files.com/APIs/gRPC-API/runtime/http-access/index.md): The JSON-over-HTTP gateway that M-Files Server runs next to its gRPC endpoint for browsers - what it is, how its routes and JSON map to the gRPC API, and why native gRPC is the better choice elsewhere.

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## Guides

- [Connect, log in and keep the session](https://developer.m-files.com/APIs/gRPC-API/guides/connect/index.md): Check the server version and capabilities anonymously, log in to a vault, read the session information, keep the session alive and log out.
- [Read the vault structure](https://developer.m-files.com/APIs/gRPC-API/guides/vault-structure/index.md): List object types, classes and property definitions, find the properties of a class, and resolve the ID of a class or property by its alias.
- [Search for documents](https://developer.m-files.com/APIs/gRPC-API/guides/search/index.md): Find the documents of a class modified in the last N days, newest first, with SearchObjects - object type, deletion, class and date conditions, sorting and a limit.
- [Read an object and its properties](https://developer.m-files.com/APIs/gRPC-API/guides/read-object/index.md): Get the latest version of an object with all its property values in one call, and print text, number, date, timestamp, lookup and multi-select lookup values.
- [Download a file](https://developer.m-files.com/APIs/gRPC-API/guides/download-file/index.md): Download a file of a document version to disk with a download session - DownloadFile_Begin, DownloadFile_ReadBlock in a loop, DownloadFile_Stop.
- [Create a document](https://developer.m-files.com/APIs/gRPC-API/guides/create-document/index.md): Upload a file with UploadTempFile and UploadTempFileCommit, then create a single-file document with a class, a title and an access control list with AddObjectWithFiles.
- [Update properties safely](https://developer.m-files.com/APIs/gRPC-API/guides/update-properties/index.md): Change property values without overwriting other users' changes - SetProperties on the version you read with fail_if_newer_version_exists, or CheckOut, SetProperties and CheckIn.
- [Change the workflow state](https://developer.m-files.com/APIs/gRPC-API/guides/workflow-state/index.md): Read a workflow's states and the transitions the user may take from an object's current state, and move the object to another state by setting its State property.
- [Page through large result sets](https://developer.m-files.com/APIs/gRPC-API/guides/paging/index.md): Visit every object that matches a search, page by page, by sorting on object ID and asking each page for the objects after the last ID of the previous one.
- [Handle errors](https://developer.m-files.com/APIs/gRPC-API/guides/errors/index.md): Catch a failed call, decode the M-Files error code from the error trailers, and tell "not found" and "access denied" apart from other errors.

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## API reference

| Book | Contents | Services | Methods |
|---|---|---|---|
| [Vault API](https://developer.m-files.com/APIs/gRPC-API/vault/index.md) | Everything an application does in a vault on behalf of a user. | 39 | 380 |
| [Administration API](https://developer.m-files.com/APIs/gRPC-API/admin/index.md) | Server and vault administration, metadata structure and user management. | 28 | 264 |
| [Server integration API](https://developer.m-files.com/APIs/gRPC-API/integration/index.md) | Services that other M-Files components and connectors call. | 11 | 68 |

- [All services](https://developer.m-files.com/APIs/gRPC-API/Reference/index.md)
- [All messages](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/index.md)
- [All enums](https://developer.m-files.com/APIs/gRPC-API/Reference/Enums/index.md)

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## Downloads

- [mfiles-grpc-api-bundle.zip](https://developer.m-files.com/APIs/gRPC-API/downloads/mfiles-grpc-api-bundle.zip): the .proto files and the runnable Python, C# and Go samples
- [mfiles-grpc-api-proto.zip](https://developer.m-files.com/APIs/gRPC-API/downloads/mfiles-grpc-api-proto.zip): the .proto files of the API
- [All downloads](https://developer.m-files.com/APIs/gRPC-API/downloads/index.md): proto files, descriptor set, manifest and indexes