Metadata-Version: 2.4
Name: durable-mcp
Version: 0.6.0
Summary: Durable Model Context Protocol (MCP) helpers for building resumable MCP servers on top of Reboot durable workflows.
Project-URL: Homepage, https://github.com/reboot-dev/mcp-python
Project-URL: Repository, https://github.com/reboot-dev/mcp-python
Project-URL: Issues, https://github.com/reboot-dev/mcp-python/issues
Author-email: Reboot <team@reboot.dev>
License:                                  Apache License
                                   Version 2.0, January 2004
                                http://www.apache.org/licenses/
        
           TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
        
           1. Definitions.
        
              "License" shall mean the terms and conditions for use, reproduction,
              and distribution as defined by Sections 1 through 9 of this document.
        
              "Licensor" shall mean the copyright owner or entity authorized by
              the copyright owner that is granting the License.
        
              "Legal Entity" shall mean the union of the acting entity and all
              other entities that control, are controlled by, or are under common
              control with that entity. For the purposes of this definition,
              "control" means (i) the power, direct or indirect, to cause the
              direction or management of such entity, whether by contract or
              otherwise, or (ii) ownership of fifty percent (50%) or more of the
              outstanding shares, or (iii) beneficial ownership of such entity.
        
              "You" (or "Your") shall mean an individual or Legal Entity
              exercising permissions granted by this License.
        
              "Source" form shall mean the preferred form for making modifications,
              including but not limited to software source code, documentation
              source, and configuration files.
        
              "Object" form shall mean any form resulting from mechanical
              transformation or translation of a Source form, including but
              not limited to compiled object code, generated documentation,
              and conversions to other media types.
        
              "Work" shall mean the work of authorship, whether in Source or
              Object form, made available under the License, as indicated by a
              copyright notice that is included in or attached to the work
              (an example is provided in the Appendix below).
        
              "Derivative Works" shall mean any work, whether in Source or Object
              form, that is based on (or derived from) the Work and for which the
              editorial revisions, annotations, elaborations, or other modifications
              represent, as a whole, an original work of authorship. For the purposes
              of this License, Derivative Works shall not include works that remain
              separable from, or merely link (or bind by name) to the interfaces of,
              the Work and Derivative Works thereof.
        
              "Contribution" shall mean any work of authorship, including
              the original version of the Work and any modifications or additions
              to that Work or Derivative Works thereof, that is intentionally
              submitted to Licensor for inclusion in the Work by the copyright owner
              or by an individual or Legal Entity authorized to submit on behalf of
              the copyright owner. For the purposes of this definition, "submitted"
              means any form of electronic, verbal, or written communication sent
              to the Licensor or its representatives, including but not limited to
              communication on electronic mailing lists, source code control systems,
              and issue tracking systems that are managed by, or on behalf of, the
              Licensor for the purpose of discussing and improving the Work, but
              excluding communication that is conspicuously marked or otherwise
              designated in writing by the copyright owner as "Not a Contribution."
        
              "Contributor" shall mean Licensor and any individual or Legal Entity
              on behalf of whom a Contribution has been received by Licensor and
              subsequently incorporated within the Work.
        
           2. Grant of Copyright License. Subject to the terms and conditions of
              this License, each Contributor hereby grants to You a perpetual,
              worldwide, non-exclusive, no-charge, royalty-free, irrevocable
              copyright license to reproduce, prepare Derivative Works of,
              publicly display, publicly perform, sublicense, and distribute the
              Work and such Derivative Works in Source or Object form.
        
           3. Grant of Patent License. Subject to the terms and conditions of
              this License, each Contributor hereby grants to You a perpetual,
              worldwide, non-exclusive, no-charge, royalty-free, irrevocable
              (except as stated in this section) patent license to make, have made,
              use, offer to sell, sell, import, and otherwise transfer the Work,
              where such license applies only to those patent claims licensable
              by such Contributor that are necessarily infringed by their
              Contribution(s) alone or by combination of their Contribution(s)
              with the Work to which such Contribution(s) was submitted. If You
              institute patent litigation against any entity (including a
              cross-claim or counterclaim in a lawsuit) alleging that the Work
              or a Contribution incorporated within the Work constitutes direct
              or contributory patent infringement, then any patent licenses
              granted to You under this License for that Work shall terminate
              as of the date such litigation is filed.
        
           4. Redistribution. You may reproduce and distribute copies of the
              Work or Derivative Works thereof in any medium, with or without
              modifications, and in Source or Object form, provided that You
              meet the following conditions:
        
              (a) You must give any other recipients of the Work or
                  Derivative Works a copy of this License; and
        
              (b) You must cause any modified files to carry prominent notices
                  stating that You changed the files; and
        
              (c) You must retain, in the Source form of any Derivative Works
                  that You distribute, all copyright, patent, trademark, and
                  attribution notices from the Source form of the Work,
                  excluding those notices that do not pertain to any part of
                  the Derivative Works; and
        
              (d) If the Work includes a "NOTICE" text file as part of its
                  distribution, then any Derivative Works that You distribute must
                  include a readable copy of the attribution notices contained
                  within such NOTICE file, excluding those notices that do not
                  pertain to any part of the Derivative Works, in at least one
                  of the following places: within a NOTICE text file distributed
                  as part of the Derivative Works; within the Source form or
                  documentation, if provided along with the Derivative Works; or,
                  within a display generated by the Derivative Works, if and
                  wherever such third-party notices normally appear. The contents
                  of the NOTICE file are for informational purposes only and
                  do not modify the License. You may add Your own attribution
                  notices within Derivative Works that You distribute, alongside
                  or as an addendum to the NOTICE text from the Work, provided
                  that such additional attribution notices cannot be construed
                  as modifying the License.
        
              You may add Your own copyright statement to Your modifications and
              may provide additional or different license terms and conditions
              for use, reproduction, or distribution of Your modifications, or
              for any such Derivative Works as a whole, provided Your use,
              reproduction, and distribution of the Work otherwise complies with
              the conditions stated in this License.
        
           5. Submission of Contributions. Unless You explicitly state otherwise,
              any Contribution intentionally submitted for inclusion in the Work
              by You to the Licensor shall be under the terms and conditions of
              this License, without any additional terms or conditions.
              Notwithstanding the above, nothing herein shall supersede or modify
              the terms of any separate license agreement you may have executed
              with Licensor regarding such Contributions.
        
           6. Trademarks. This License does not grant permission to use the trade
              names, trademarks, service marks, or product names of the Licensor,
              except as required for reasonable and customary use in describing the
              origin of the Work and reproducing the content of the NOTICE file.
        
           7. Disclaimer of Warranty. Unless required by applicable law or
              agreed to in writing, Licensor provides the Work (and each
              Contributor provides its Contributions) on an "AS IS" BASIS,
              WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
              implied, including, without limitation, any warranties or conditions
              of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
              PARTICULAR PURPOSE. You are solely responsible for determining the
              appropriateness of using or redistributing the Work and assume any
              risks associated with Your exercise of permissions under this License.
        
           8. Limitation of Liability. In no event and under no legal theory,
              whether in tort (including negligence), contract, or otherwise,
              unless required by applicable law (such as deliberate and grossly
              negligent acts) or agreed to in writing, shall any Contributor be
              liable to You for damages, including any direct, indirect, special,
              incidental, or consequential damages of any character arising as a
              result of this License or out of the use or inability to use the
              Work (including but not limited to damages for loss of goodwill,
              work stoppage, computer failure or malfunction, or any and all
              other commercial damages or losses), even if such Contributor
              has been advised of the possibility of such damages.
        
           9. Accepting Warranty or Additional Liability. While redistributing
              the Work or Derivative Works thereof, You may choose to offer,
              and charge a fee for, acceptance of support, warranty, indemnity,
              or other liability obligations and/or rights consistent with this
              License. However, in accepting such obligations, You may act only
              on Your own behalf and on Your sole responsibility, not on behalf
              of any other Contributor, and only if You agree to indemnify,
              defend, and hold each Contributor harmless for any liability
              incurred by, or claims asserted against, such Contributor by reason
              of your accepting any such warranty or additional liability.
        
           END OF TERMS AND CONDITIONS
        
           APPENDIX: How to apply the Apache License to your work.
        
              To apply the Apache License to your work, attach the following
              boilerplate notice, with the fields enclosed by brackets "[]"
              replaced with your own identifying information. (Don't include
              the brackets!)  The text should be enclosed in the appropriate
              comment syntax for the file format. We also recommend that a
              file or class name and description of purpose be included on the
              same "printed page" as the copyright notice for easier
              identification within third-party archives.
        
           Copyright [yyyy] [name of copyright owner]
        
           Licensed under the Apache License, Version 2.0 (the "License");
           you may not use this file except in compliance with the License.
           You may obtain a copy of the License at
        
               http://www.apache.org/licenses/LICENSE-2.0
        
           Unless required by applicable law or agreed to in writing, software
           distributed under the License is distributed on an "AS IS" BASIS,
           WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
           See the License for the specific language governing permissions and
           limitations under the License.
License-File: LICENSE
Keywords: durable,mcp,model-context-protocol,reboot,workflows
Classifier: Development Status :: 2 - Pre-Alpha
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: Apache Software License
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.12
Classifier: Topic :: Internet :: WWW/HTTP
Classifier: Topic :: Software Development :: Libraries
Classifier: Typing :: Typed
Requires-Python: >=3.12.11
Requires-Dist: mcp==1.21.0
Requires-Dist: reboot==0.40.1
Requires-Dist: uuid7-standard>=1.1.0
Provides-Extra: dev
Requires-Dist: build; extra == 'dev'
Requires-Dist: mypy==1.2.0; extra == 'dev'
Requires-Dist: pytest==8.4.1; extra == 'dev'
Requires-Dist: twine; extra == 'dev'
Requires-Dist: types-protobuf>=4.24.0.20240129; extra == 'dev'
Description-Content-Type: text/markdown

# Reboot *Durable* MCP

A framework for building _durable_ MCP servers.

* Takes advantage of the protocols ability to resume after
  disconnection, e.g., due to the server getting rebooted.

* Any existing requests will be retried safely using Reboot workflows.

* Using Reboot you can run multiple replicas of your server, and
  session messages will always be routed to the same replica.

### Requirements
- macOS or Linux
- Python >= 3.12.11
- Docker

### Install

We recommend using `uv`, as it will manage the version of Python for
you. For example, to start a new project in the directory `foo`:

```console
uv init --python 3.12.11 .
uv add durable-mcp
```

Activate the `venv`:

```console
source .venv/bin/activate
```

Make sure you have Docker running:

```console
docker ps
```

### Building an MCP server

Instead of using `FastMCP` from the MCP SDK, you use
`DurableMCP`. Here is a simple server to get you started:

```python
import asyncio
from reboot.aio.applications import Application
from reboot.mcp.server import DurableContext, DurableMCP
from reboot.std.collections.v1.sorted_map import SortedMap

# `DurableMCP` server which will handle HTTP requests at path "/mcp".
mcp = DurableMCP(path="/mcp")


@mcp.tool()
async def add(a: int, b: int, context: DurableContext) -> int:
    """Add two numbers and also store result in `SortedMap`."""
    result = a + b
    await SortedMap.ref("adds").insert(
        context,
        entries={f"{a} + {b}": f"{result}".encode()},
    )
    return result


async def main():
    # Reboot application that runs everything necessary for `DurableMCP`.
    await mcp.application().run()


if __name__ == '__main__':
    asyncio.run(main())
```

You can run the server via:

```console
rbt dev run --python --application=path/to/main.py --working-directory=. --no-generate-watch
```

While developing you can tell `rbt` to restart your server when you
modify files by adding one or more `--watch=path/to/**/*.py` to the
above command line.

We recommend you move all of your command line args to a `.rbtrc`:

```bash
# This file will aggregate all of the command line args
# into a single command line that will be run when you
# use `rbt`.
#
# For example, to add args for running `rbt dev run`
# you can add lines that start with `dev run`. You can add
# one or more args to each line.
dev run --no-generate-watch
dev run --python --application=path/to/your/main.py
dev run --watch=path/to/**/*.py --watch=different/path/to/**/*.py
```

Then you can just run:

```console
rbt dev run
```

### Testing your MCP server

You can use the [MCP
Inspector](https://modelcontextprotocol.io/legacy/tools/inspector) to
test out the server, or create a simple client.

```python
import asyncio
from reboot.mcp.client import connect, reconnect

URL = "http://localhost:9991"


async def main():
    # `connect()` is a helper that creates a streamable HTTP client
    # and session using the MCP SDK. You can also write a client that
    # directly uses the MCP SDK, or use any other MCP client library!
    async with connect(URL + "/mcp") as (
        session, session_id, protocol_version
    ):
        print(await session.list_tools())
        print(await session.call_tool("add", arguments={"a": 5, "b": 3}))


if __name__ == '__main__':
    asyncio.run(main())
```

### Performing a side-effect "at least once"

Within your tools (and soon within your prompts and resources too),
you can perform a side-effect that is safe to try one or more times
until success using `at_least_once`. Usually what makes it safe to
perform one or more times is that you can somehow do it
_idempotently_, e.g., passing an idempotency key as part of an API
call. Use `at_least_once` for this, for example:

```python
from reboot.aio.workflows import at_least_once
from reboot.mcp.server import DurableContext, DurableMCP


# `DurableMCP` server which will handle HTTP requests at path "/mcp".
mcp = DurableMCP(path="/mcp")


@mcp.tool()
async def add(a: int, b: int, context: DurableContext) -> int:

    async def do_side_effect_idempotently() -> int:
        """
        Pretend that we are doing a side-effect that we can try
        more than once because we can do it idempotently, hence using
        `at_least_once`.
        """
        return a + b

    result = await at_least_once(
        "Do side-effect _idempotently_",
        context,
        do_side_effect_idempotently,
        type=int,
    )

    # ...
```

### Performing a side-effect "at most once"

Within your tools (and soon within your prompts and resources too),
you can perform a side-effect that can _only_ be **tried** once using
`at_most_once` (if you can safely use `at_least_once` always prefer
it). Here's an example of `at_most_once`:

```python
from reboot.aio.workflows import at_least_once
from reboot.mcp.server import DurableContext, DurableMCP


# `DurableMCP` server which will handle HTTP requests at path "/mcp".
mcp = DurableMCP(path="/mcp")


@mcp.tool()
async def add(a: int, b: int, context: DurableContext) -> int:

    async def do_side_effect() -> int:
        """
        Pretend that we are doing a side-effect that we can only
        try to do once because it is not able to be performed
        idempotently, hence using `at_most_once`.
        """
        return a + b

    # NOTE: if we reboot, e.g., due to a hardware failure, within
    # `do_side_effect()` then `at_most_once` will forever raise with
    # `AtMostOnceFailedBeforeCompleting` and you will need to handle
    # appropriately.
    result = await at_most_once(
        "Do side-effect",
        context,
        do_side_effect,
        type=int,
    )

    # ...
```

### Debugging

Start by enabling debug logging:

```python
mcp = DurableMCP(path="/mcp", log_level="DEBUG")
```

The MCP SDK is aggressive about "swallowing" errors on the server side
and just returning "request failed" so we do our best to log stack
traces on the server. If you find a place where you've needed to add
your own `try`/`catch` please let us know we'd love to log that for
you automatically.

### Supported client --> server _requests_:
- [x] `initialize`
- [x] `tools/call`
- [x] `tools/list`
- [x] `prompts/get`
- [x] `prompts/list`
- [x] `resources/list`
- [x] `resources/read`
- [x] `resources/templates/list`
- [ ] `resources/subscribe`
- [ ] `resources/unsubscribe`
- [ ] `completion/complete`
- [ ] `logging/setLevel`

### Supported client --> server _notifications_:
- [x] `notifications/initialized`
- [ ] `notifications/progress` (for server initiated requests, e.g., elicitation)
- [ ] `notifications/roots/list_changed`

### Supported client <-- server _requests_:
- [x] `elicitation/create`
- [ ] `roots/list`
- [ ] `sampling/createMessage`

### Supported client <-- server _notifications_:
- [x] `notifications/progress`
- [x] `notifications/message`
- [x] `notifications/prompts/list_changed`
- [x] `notifications/resources/list_changed`
- [x] `notifications/tools/list_changed`
- [ ] `notifications/resources/updated`

### Supported client <--> server _notifications_:
- [ ] `notifications/cancelled`

### TODO:
- [x] Auth pass through to MCP SDK
- [ ] Add Auth examples
- [ ] Adding tools, resources, and prompts dynamically
- [ ] Add examples of how to test via `Reboot().start/up/down/stop()`
- [ ] Add example of rebooting server using MCP Inspector version [0.16.7](https://github.com/modelcontextprotocol/inspector/releases/tag/0.16.7) which includes [modelcontextprotocol/inspector#787](https://github.com/modelcontextprotocol/inspector/pull/787)
- [ ] `yapf`
- [ ] Pydantic `state` for each session

### Contributing

First grab all dependencies:

```console
uv sync --extra dev
```

Activate the `venv`:

```console
source .venv/bin/activate
```

Generate code:

```console
rbt generate
```

Make sure you have Docker running:

```console
docker ps
```

Make your changes and run the tests:

```console
pytest tests
```
