Commit graph go-sdk/mcp/mcp_test.go
Author SHA1 Message Date
Robert Findley
204b59483b
mcp,design: revert 'content' back to an interface type (#29)
After some experience with the flattened version of Content, we see that
it can easily lead to incorrect usage and is a harder API to read.
Therefore, this CL changes back to a design similar to what we had prior
to https://go.dev/cl/672415, though opting to promote content
unmarshalling to the protocol types that use it, which leads to an
overall simpler api.
2025-06-25 13:09:05 -04:00
Jonathan Amsterdam
3da831b0c9
mcp: move to 2025-06-18 schema (#8)
* mcp: move to 2025-06-18 schema

Add types and fields for the latest MCP schema.

The main challenge here was dealing with the presence of _meta fields
on many types, like Tool, Prompt and Resource.

- Distinguish between the _meta field of a request's params, which
  includes a progress token, from the _meta field on other types,
  which is simply a map.

- Redefine GetMeta to return a pointer to the map. We wanted to avoid
  that, but I don't see a clean way to do so. An alternative would be
  to have GetMeta return a map, and SetMeta to set it.

- Provide GetProgressToken for requests only (not notifications or other
  types).

- Still to do: deal with the meta and annotation fields of ContentBlock,
  which are currently duplicated for Resource and ResourceContents.

* Meta and progress token redesign
2025-06-25 09:48:33 -04:00
Jonathan Amsterdam
a6ec3f5f4e internal/mcp: simplify prompt API
Remove NewServerPrompt.

Schema inference is irrelevant for prompts.
All arguments are strings.
So using a struct is not as valuable as with tools.
The only advantage is catching misspellings at compile time.
It's not worth it.

Change-Id: I45aaa5d55c8940cc9e32dc277bd543f79d932519
Reviewed-on: https://go-review.googlesource.com/c/tools/+/682797
Reviewed-by: Robert Findley <rfindley@google.com>
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2025-06-20 07:28:04 -07:00
Rob Findley
927070053a internal/mcp: avoid JSON nulls on the wire
Add a test that checks for JSON null on the wire, and fix two categories
of bugs leading to null:

1. In many places, we could pass typed nil where we shouldn't have. Add
   an orZero helper to avoid typed nills.
2. When listing roots, we should avoid nil.

Fixes golang/go#74105

Change-Id: I061420487dbfcbf9016cb94b39bd72270e871c0e
Reviewed-on: https://go-review.googlesource.com/c/tools/+/682675
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2025-06-18 12:32:33 -07:00
Rob Findley
1fead0ba64 internal/mcp: rename Stream->Connection
After implementing the Streamable transport, it is apparent to me that
the name 'Stream' is confusing, as it can refer either to a stream in
the streamable transport, or to a JSON-RPC stream.

But the name 'Connection' is available, and a natural name for the
result of the Transport.Connect interface method. Therefore, rename
Stream to Connection, and update the streamable implementation to refer
to its HTTP connections as 'streams', consistent with other SDKs.

Change-Id: Ica55f84caabcbfa5a2fe029cc0c2db57da574875
Reviewed-on: https://go-review.googlesource.com/c/tools/+/682376
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2025-06-17 17:55:11 -07:00
Rob Findley
9453d6bf6c internal/mcp: rename NewXXX->NewServerXXX
The NewTool and NewPrompt constructors were unidiomatic, because they
returned a ServerTool and ServerPrompt, respectively, rather than a Tool
and Prompt. Rename to be consistent with the constructed object name.

Change-Id: Ife3f16f783368401f792660c4272e1bb5ae61638
Reviewed-on: https://go-review.googlesource.com/c/tools/+/682375
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2025-06-17 17:54:58 -07:00
Sam Thanawalla
11b17f5858 internal/mcp: add NotifyProgress
This CL adds a NotifyProgress function and a ProgressNotificationHandler
to enable progress sending and handling.
Subsequent CL's to follow to handle progress updates for other methods such as list or readresource.

Change-Id: Ifcc422e6f6231d7d773d5432c1cf64032d796709
Reviewed-on: https://go-review.googlesource.com/c/tools/+/681116
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2025-06-12 09:59:05 -07:00
Jonathan Amsterdam
f211cc8e4a internal/mcp: reorganize the tool API, keeping generics
CallToolParams.Arguments is any.

Clients can send whatever they want.

Tool authors who create their own ToolHandler (bypassing NewTool)
will receive the arguments as a map[string]any which has been
validated against the input schema.

Tool authors who call NewTool can choose the type that the arguments
unmarshal into.

There is no double-unmarshaling and no downcasting.

There is no way for tool authors to avoid the unmarshal, and no way to
avoid the validation unless the omit an input schema, which is probably
bad for LLMs. If tool authors want this optimization, we can provide
it later.

Change-Id: Ieb201e56c7fb8a23bb1a93b27e946630ec9e79ad
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2025-06-10 04:57:48 -07:00
Jonathan Amsterdam
c1524fe934 internal/mcp: implement resource templates
Provide support for resource templates on the client and server.

Adding, removing and listing resource templates looks just like those
operations on resources.

Although the spec provides no guidance on the unique ID for resource
templates, we follow most existing SDKs, as well as the parallel with
resources, and index on the URI template rather than the name.

As the spec recommends, the server verifies an incoming URI in a
ReadResource request against its list of resources and resource
templates, to make sure the URI came from one of them. The main
technical challenge here is the need to check that a URI template could
have produced a particular URI.

I wrote a very simplified version of this check. At some point
we should switch to github.com/yosida95/uritemplate/v3.

Change-Id: I1e34dd01c8f2171123c68c045ad62f5e85c05e7c
Reviewed-on: https://go-review.googlesource.com/c/tools/+/680158
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2025-06-09 10:59:01 -07:00
Jonathan Amsterdam
a07ce11b37 internal/mcp: validate tool input schemas
A tool now validates its input with its InputSchema.

Change schema inference to allow explicit nulls for fields of
pointer type.

We assume the schema has no external references. For example, the
following schema cannot be handled:

  {
    "$ref": "https://example.com/other.json"
  }

Schemas with internal references, like to a "$defs", are fine.

Change-Id: I6ee7c18c2c5cb609df0b22a66da986f7ea64bbe4
Reviewed-on: https://go-review.googlesource.com/c/tools/+/670676
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2025-06-04 07:51:59 -07:00
Jonathan Amsterdam
0d0c48a468 internal/mcp: middleware on the sending side
Implement sending middleware.

Sending middleware is useful for adding tracing, progress tokens,
and so on.

Change-Id: I0acab2550f0212d549c4adbcf1ebf425a9486df6
Reviewed-on: https://go-review.googlesource.com/c/tools/+/676355
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2025-06-02 13:16:02 -07:00
Jonathan Amsterdam
19d58e6955 internal/mcp: simplify session type params
Write a separate constraint for ClientSession | ServerSession,
and change the pointerness of the type parameter.

There is still a dynamic cast, but overall I think this is a bit
simpler:

- The exported types have the more readable constraint "Session"
  instead of "ClientSession | ServerSession".

- We can put the unexported methods in Session instead of needing a
  separate interface (previously "session").

- This CL enables a simplified treatment of sending middleware, in
  the next CL.

Change-Id: I41184fe93ea201d1da29dbfba26ac59f93771277
Reviewed-on: https://go-review.googlesource.com/c/tools/+/676175
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2025-06-02 10:51:53 -07:00
Rob Findley
04ca8ac03b internal/mcp: generic handling of CallToolParams
Make Tool APIs future-proof by pushing generics into CallToolParams, and
using CallToolParams throughout. This has several advantages:

- We no longer need the awkward CallToolOptions type, which is almost
  but not quite like CallToolParams.
- NewTool no longer needs to define its own handler type: it accepts a
  ToolHandler[TArgs]. This also means its signature is future-proof.

Additionally, provide a `CallTool` helper (the analog of NewTool) to
serve as a more strongly typed variant of `ClientSession.CallTool`.

+ design, protocol generation

Change-Id: I80172a25bc50734dae84a541aa4776ed9161694e
Reviewed-on: https://go-review.googlesource.com/c/tools/+/676495
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2025-06-02 07:45:36 -07:00
Jonathan Amsterdam
a627a4a2dd internal/mcp: add resource conformance test
This uncovered a problem in how we represent resource results:
contents is a slice, not a single value.

I tried to use a file resource, but the server->client ListRoots
call didn't work because synthetic responses aren't supported.
Left a TODO.

I enhanced the hello example so I that could use the MCP Inspector to
work with resources.

The falseSchema change fixes a potential bug where schemas are
re-used, which is disallowed.

Change-Id: I1f0198043cb6221c2a03f4f83aa0bafbc71167f4
Reviewed-on: https://go-review.googlesource.com/c/tools/+/677136
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2025-05-29 11:59:43 -07:00
Rob Findley
e2bbd8002d internal/mcp: add JSON conformance tests, and fix some bugs
Add the beginnings of some testdata-driven conformance tests that check
JSON-level compatibility of SDK messages, and fix some bugs in our JSON
message handling:

- "params" can be missing
- "_meta" should not be null
- lists of tools/prompts/resources should not be null

In order to implement this, we need to be able to know when the server
is done processing messages. In general, this is a hard problem; for
gopls we do this with a complicated system of progress reporting and
accounting. However, the new synctest package makes this trivial, as we
can call synctest.Wait to detect when the server is idle. Therefore,
this test requires 1.25 (it uses synctest.Test, added in 1.25, and so
can't run at 1.24 with GOEXPERIMENT=synctest).

Change-Id: I97fa28b56868340ece266a58e1eb3c3bf8cfe0e9
Reviewed-on: https://go-review.googlesource.com/c/tools/+/676538
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2025-05-28 10:00:05 -07:00
Jonathan Amsterdam
7130f0f081 internal/mcp: meta and progress token
Meta is a struct that contains a map[string]any, and a ProgressToken
field.

Each Params and Result type has a Meta as a value field.

Meta marshals and unmarshals specially, so the ProgressToken field
becomes part of the map. The marshalling code is generalized in
anticipation of every Params and Result growing a map of additional
properties.

Change-Id: I6d2f34270d33501c96437f24f91ef3e51d20d955
Reviewed-on: https://go-review.googlesource.com/c/tools/+/674956
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2025-05-27 12:53:53 -07:00
Jonathan Amsterdam
b1780319e4 internal/mcp: future-proof prompt handling
Pass GetPromptParams as needed, in case that type ever gets additional
properties.

Change-Id: I83fa37bb2af5633a8c2bcdc47a85c3030dfe70fb
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2025-05-22 15:06:03 -07:00
Jonathan Amsterdam
edda031578 internal/mcp: implement logging
Provide a ServerSession method that directly implements the spec
method.

Also provide a custom slog.Handler that writes a notification on each
log call. It uses a slog.JSONHandler to format the message as JSON, then
adds the additional fields of LoggingMessageParams.

I decided that the direct method should handle levels, since that is
in the spec, but that rate-limiting is an extra feature, so is only
provided in the slog handler.

Change-Id: I1190ca124e992e61fb633ac52ee3492c8e6d99c9
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2025-05-22 15:02:13 -07:00
Jonathan Amsterdam
ce5b6cd926 internal/mcp: add notifications
Add notification logic for intialization and list changes.

Change-Id: I1d392bb49d5995f2046c400da955a033ab2715ce
Reviewed-on: https://go-review.googlesource.com/c/tools/+/673775
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2025-05-21 16:01:46 -07:00
Jonathan Amsterdam
9bcc6c758f internal/mcp: sampling
Implement sampling (the CreateMessage method).

Change-Id: Ie44a671dd62831122b25cd7386b5bfcdece7ff60
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2025-05-19 11:15:58 -07:00
Jonathan Amsterdam
bac1b78b4a internal/mcp: client middleware
Implement middleware for clients.

Make the middleware types generic so we can factor out code
from both peers.

I was able to make the request handler generic, with one weird trick
(see handleRequest).

The first three declarations of shared.go, and a few others as well,
are copied unchanged from middleware.go.

Change-Id: Ib3239d8fcfda022ddb5b554c38cff4cdbc3704c1
Reviewed-on: https://go-review.googlesource.com/c/tools/+/673635
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2025-05-19 11:15:45 -07:00
Jonathan Amsterdam
8361df724d internal/mcp: add the FileResourceHandler method
Provide secure reading of files on the local filesystem.

There are subtleties in path manipulation on Windows that I don't fully
understand, so I defer that work for now.

Change-Id: Ic11f4617dde4ac0b31ccd5b0a772bb2f56db026f
Reviewed-on: https://go-review.googlesource.com/c/tools/+/673196
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2025-05-19 11:15:23 -07:00
Jonathan Amsterdam
1323fb5216 internal/mcp: dispatcher middleware
Implement the dispatcher middleware framework, allowing users to
wrap method dispatching with their own code.

The Dispatcher functions have an untyped params arg, but expect its
value to be a typed, unmarshaled XXXParams struct. That required
splitting the elegant dispatch[P, R] function into two parts, one
to do the unmarshaling and one to call the method. The nicest way
I could find to do that was to map from method names to a pair
of functions, one to unmarshal and one to call. We could also write
it as two switches on method name, which would require less machinery
but would duplicate the list of method names, already a tad fragile
because they are literal strings.

I also exported the initialize params and result, so user Dispatchers
could access them. All Params and Result types will have to be exported
for that reason.

Change-Id: Ie2c95cc17b4ef3d3d095dccdadb294e5f1590796
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2025-05-16 11:24:52 -07:00
Rob Findley
a8b98da480 internal/mcp: reinstate ClientSession
Add a logical client session type back to the SDK, to bring it closer to
the design. Also, remove 'ConnectionOptions', which is better
implemented using middleware, and reimplement logging as a
LoggingTransport middleware, which is also added to the design.

Change-Id: I908b4f837d513ffc60ae5b6171a31519cffafebc
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2025-05-14 12:41:58 -07:00
Rob Findley
dbf57af24b internal/mcp: rename LocalTransport->InMemoryTransport, and document
Update the design to mention our in-memory transport, since it is
generally useful, and update the implementation to use distinct types
for InMemoryTransport and StdIOTransport (the fact that they are both
implemented as an io.ReadWriteCloser is an implementation detail).

Change-Id: I8228ccf2092a56a730c113c4db105fb492cce112
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2025-05-14 10:11:26 -07:00
Rob Findley
ac828d5a82 internal/mcp: rename ServerConnection->ServerSession
Bring the Server implementation up to date with the spec by renaming
ServerConnection to ServerSession. Also update variable names, which
were in various states of disarray from the multiple renamings of this
type.

Change-Id: I4aec883db6d0500fb91e6daa51b702614877cf8a
Reviewed-on: https://go-review.googlesource.com/c/tools/+/672655
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2025-05-14 10:10:28 -07:00
Jonathan Amsterdam
81a8ece2dd internal/mcp: resource tweaks
Get the name and signature of the handler right.

Change-Id: I743aaaee45cc07a741ab8ad16e90e1b1d5519b64
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2025-05-14 08:50:33 -07:00
Jonathan Amsterdam
6394485a3d internal/mcp: change CallTool signature
CallTool takes a tool name, arguments, and an options struct.

Also, pass the params to ToolHandler.

Update the design doc accordingly.

Change-Id: I21b7995b607bea976ad708ebb6ac0716018f39cb
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2025-05-14 06:23:21 -07:00
Jonathan Amsterdam
4721f501df internal/mcp: change function signatures match design doc
To ensure backward compatibility, every method in the spec now takes a
*Params struct and returns a *Result struct.

CallTools is an exception: we'll change that in the next CL.

Change-Id: I58835239c67582401b8c9c2d070702d270131c08
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2025-05-14 06:23:12 -07:00
Jonathan Amsterdam
02fa1b3ea6 internal/mcp: pointerize all the things
Use pointers for the protocol's struct types, to future-proof against
them getting large.

Change-Id: I55b204080a41c8140539697ba264e502e912e613
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2025-05-14 06:22:56 -07:00
Rob Findley
dac5be2c50 internal/mcp: simplify content
Now that the protocol package is merged into the mcp package, clean up
the higher level 'Content' union types, in favor of types constructors.

Change-Id: I37bedb0ff0a296eef799ba65c37ca7f94ee1dbbe
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2025-05-13 15:03:25 -07:00
Rob Findley
4f6510b9ae internal/mcp: merge the protocol package into mcp
In accordance with the updated design, merge the protocol package into
the mcp package. To do so, rename protocol.Content to WireContent and
protocol.ResourceContents to WireResource.

Also, remove some stray logging in readResource.

Change-Id: I76f61ce8d67dd3ac520ef2e1959ade0a0785a480
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2025-05-13 14:43:46 -07:00
Jonathan Amsterdam
1ae23e7031 internal/mcp: implement resources
Implementation of resources.

This follows the design sketched in design/design.md, except for
Server.FileResourceHandler, which will be in a forthcoming CL.

As the spec recommends, the server verifies an incoming URI from the
client against its list of resources, to make sure the URI came from one
of them.

Some things that aren't in the design doc:
- I provide an exported function that creates a "resource not found"
  jsonrpc2.WireEror error for server authors to return.
  A wrinkle: the MCP spec defines the error code for
  "resource not found" as -32002 [1]. That code is reserved for use
  by implementations of JSON-RPC, not applications. That matters to us
  because our JSON-RPC implementation already uses that code for the
  "server closing" error. I filed a bug against MCP about it [2] and
  chose a different code for the "resource not found" error.

- As a slight convenience, I fill in some fields in the
  ReadResourceResult if the handler doesn't set them.

[1] https://modelcontextprotocol.io/specification/2025-03-26/server/resources#error-handling
[2] https://github.com/modelcontextprotocol/modelcontextprotocol/issues/509

Change-Id: I06153da982ea00748a3691ded923448a880cea2a
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2025-05-13 11:39:49 -07:00
Jonathan Amsterdam
5004d3e1bb internal/mcp: implement roots
Add support for roots.

Change-Id: Ia50abc88f0047238272d698f30ce615b1a8fd486
Reviewed-on: https://go-review.googlesource.com/c/tools/+/671360
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Reviewed-by: Robert Findley <rfindley@google.com>
2025-05-13 07:52:49 -07:00
Jonathan Amsterdam
37ae90648b internal/mcp/protocol: featureSet[T]
What the spec calls "lists" of features (tools, prompts and so on)
are actually sets. Define a common data structure we can use to
implement all of them, and use it for server tools and prompts.

Change-Id: I257d0776b87a746ff23cd49ebcc7b317f4ea65e1
Reviewed-on: https://go-review.googlesource.com/c/tools/+/671359
Reviewed-by: Robert Findley <rfindley@google.com>
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2025-05-12 11:03:35 -07:00
Rob Findley
347a1a0078 internal/mcp: rename ClientConnection to ServerConnection
It's too confusing that you send server requests through the Client, and
send client requests through the ClientConnection. Rename
ClientConnection to ServerConnection, so that the types on the
server side of the control diagram start with 'Server'.

Change-Id: Idfd27af464a9296a2341cd23b2075cd9d0eb6b45
Reviewed-on: https://go-review.googlesource.com/c/tools/+/670538
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Reviewed-by: Jonathan Amsterdam <jba@google.com>
2025-05-07 10:17:38 -07:00
Jonathan Amsterdam
e0e304e51e internal/mcp: rename Make* to New*
Change-Id: I8d3d2ca125b7c24dd265937c4fe910ea823ab811
Reviewed-on: https://go-review.googlesource.com/c/tools/+/670537
Reviewed-by: Robert Findley <rfindley@google.com>
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2025-05-07 09:32:55 -07:00
Jonathan Amsterdam
f8098af1c5 internal/mcp: NewClient takes Transport
Pass the client Transport to NewClient instead of Connect.
Combine the ConnectionOptions with the ClientOptions.

Change-Id: I3acd6cf6d5bf46666742f2a73e2acaef2057ea77
Reviewed-on: https://go-review.googlesource.com/c/tools/+/670215
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2025-05-06 12:19:25 -07:00
Rob Findley
8efb54691d internal/mcp/protocol: move out of mcp/internal, as it's used in the API
The generated protocol package is part of the SDK API, so it shouldn't
be internal.

Change-Id: I5306af48019b1599707b939b348eb6ae4f766ca9
Reviewed-on: https://go-review.googlesource.com/c/tools/+/670356
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2025-05-06 10:18:38 -07:00
Jonathan Amsterdam
15e0c9ef02 internal/mcp: move jsonschema out of mcp/internal
The jsonschema package is part of of the API of the mcp package,
so it should not be internal.

Change-Id: I9520797837329fc2cda09c2f46ec4d48d031b9d3
Reviewed-on: https://go-review.googlesource.com/c/tools/+/669996
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Reviewed-by: Robert Findley <rfindley@google.com>
2025-05-05 13:17:44 -07:00
Jonathan Amsterdam
3d33fafc5d jsonschema: pre-compile regexps
This is the first CL that deals with the process of preparing a schema for validation.

Perform some basic checks on the scheme. Along the way, compile regexps and store
them in the schema for use during validation.

Change-Id: I0e5e6ce28656dcecb6d2d4b2fdc98998fa05b6f1
Reviewed-on: https://go-review.googlesource.com/c/tools/+/669696
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2025-05-05 12:29:58 -07:00
Jonathan Amsterdam
7a76f3502a mcp: remove ServerConnection
Remove ServerConnection.
- It's not in typescript or mcpgo APIs.
- Amortizing a client over multiple servers doesn't have any value.

Change-Id: I725b42569733d6836864d96b16898a10ae91e570
Reviewed-on: https://go-review.googlesource.com/c/tools/+/669575
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Reviewed-by: Robert Findley <rfindley@google.com>
2025-05-02 13:30:38 -07:00
Rob Findley
bf608eeeae internal/mcp: clean up handling of content
Add support for all content types, and formalize the conversion of
content to and from the wire format (as a discriminated union).

Change-Id: I93678ce98c02176a524d2c82425fb1267ad68bf0
Reviewed-on: https://go-review.googlesource.com/c/tools/+/669135
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2025-05-01 19:15:30 -07:00
Rob Findley
af4d138732 internal/mcp: support prompts
Add support for 'prompts/list' and 'prompts/get', and registering
prompts on the server using AddPrompts. Add a 'MakePrompt' helper to
construct prompts from a prompt handler using reflection.

Change-Id: I479cb9c9b99313cca99640c1f5ea1939363759e6
Reviewed-on: https://go-review.googlesource.com/c/tools/+/669015
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2025-05-01 18:43:44 -07:00
Rob Findley
e082a340be internal/mcp: add tool and schema options
Implement variadic options for building tools and schemas, to allow
easier customization of tool input schemas.

Also, make fields required, unless they are marked as "omitempty".

Change-Id: I7a29258fae3ec5e7ea4906ed30ed6750979de962
Reviewed-on: https://go-review.googlesource.com/c/tools/+/668955
Reviewed-by: Jonathan Amsterdam <jba@google.com>
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2025-05-01 18:41:25 -07:00
Jonathan Amsterdam
3434e57007 internal/mcp/internal/jsonschema: schema definition
The first of several CLs providing JSON Schema validation.

Replace the existing Schema type with one that has all the keywords
of the most current version of the JSON Schema spec, called 2020-12.

The 2020-12 spec can be represented type-safely in Go with one exception:
the "type" keyword can be either a string or a []string. To handle this
safely, both Type and Types fields are defined. Custom
JSONMarshal/Unmarshal methods handle the conversion. We need the
unmarshal anyway because "true" and "false" are valid schemas.

Unfortunately, the MCP spec uses the older "draft7" version of JSON
Schema, but the two are close enough for code generation to work.
I confirmed that the protocol generator produces the identical output.

Change-Id: I44f6ea2f3a3f8498979946f69dfb7f50afa1acad
Reviewed-on: https://go-review.googlesource.com/c/tools/+/667855
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Reviewed-by: Alan Donovan <adonovan@google.com>
2025-04-25 08:33:53 -07:00
Rob Findley
14b18b2645 internal/mcp: implement cancellation
Use the existing jsonrpc2 preemption mechanism to implement MCP
cancellation.

This was mostly straightforward, except where I got confused about ID
unmarshaling. Leave a note about using omitempty when it is available.

Change-Id: I13e073f08c5d5c2cc78d882da4e6ff47f09fb340
Reviewed-on: https://go-review.googlesource.com/c/tools/+/667578
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2025-04-23 19:15:39 -07:00
Rob Findley
fe938f6eb7 internal/mcp: implement ping, and test request interleaving
Also validate that requests observe the lifecycle rules defined in the
spec.

Change-Id: I302282f81e053e76926e0bb295f7dbf8d526f02d
Reviewed-on: https://go-review.googlesource.com/c/tools/+/667575
Reviewed-by: Jonathan Amsterdam <jba@google.com>
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2025-04-23 19:15:29 -07:00
Rob Findley
ef446f82d7 internal/mcp: implement HTTP SSE transport
Add support for SSE transport, as defined by version 2024-11-05 and
2025-03-26 of the MCP spec.

In order to achieve this, the jsonrpc2 stream must be abstracted so that
we can implement it across multiple HTTP requests. This required some
refactoring of the jsonrpc2_v2 package, so that we can avoid the
Dialer/Binder interfaces and construct the Connection directly from its
constituent primitives.

Change-Id: Id627b5b5a474d92f2c613cfad904d14611e7c768
Reviewed-on: https://go-review.googlesource.com/c/tools/+/667475
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Reviewed-by: Jonathan Amsterdam <jba@google.com>
2025-04-23 19:15:20 -07:00
Rob Findley
1204b93a85 internal/mcp: add batching support
Update the jsonrpc2 MCP framer to support both incoming and outgoing
batches. In order to achieve this, we must correlate the framed Reader
and Writer, which is not explicitly supported by the jsonrpc2 API, but
does work. A note is left to revisit the Framer interface.

Change-Id: If060cb5822da067833db20d58f5f112a0528da91
Reviewed-on: https://go-review.googlesource.com/c/tools/+/667295
Reviewed-by: Jonathan Amsterdam <jba@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2025-04-22 14:39:09 -07:00