Add a missing CommandTransport that communicates with a sidecar process
over newline-delimited stdin/stdout, the counterpart to the existing
StdIOTransport.
Add a test using the usual TestMain trick.
Change-Id: I170ba78faf6b6d7fca7da1af11bf92e919b11ed5
Reviewed-on: https://go-review.googlesource.com/c/tools/+/668895
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
Export the Transport interface, as there's no reason users shouldn't be
able to define their own transports: they are just bidirectional
streams.
Also, add a godoc example for basic Server usage.
Finally, remove some TODOs that existed due to a bad merge: they are
related to the (as yet unsubmitted) streamable HTTP transport.
Change-Id: Id669793fc80630e667d50611fe2876d09125a025
Reviewed-on: https://go-review.googlesource.com/c/tools/+/668675
TryBot-Bypass: Robert Findley <rfindley@google.com>
Reviewed-by: Sam Thanawalla <samthanawalla@google.com>
Auto-Submit: Robert Findley <rfindley@google.com>
Based on my understanding, the getServer function is used to determine
which MCP server should be serving the session.
User might want to dynamically determine which MCP server to serve when
a new request comes in. In mcp/examples, two MCP servers are created
serving at the same port but under different URL "/greeter1",
"/greeter2". The MCP client will reach out to different URLs for
different MCP servers.
As a TODO, if the getServer() returns nil, the program will crash when
handing MCP request.
Change-Id: I4431266666e9ea28118e827a94eb1359b1fb3a81
Reviewed-on: https://go-review.googlesource.com/c/tools/+/668535
Reviewed-by: Robert Findley <rfindley@google.com>
Auto-Submit: Hongxiang Jiang <hxjiang@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Add a bit more theory around SSE transport shutdown, and some
documentation of the SSE transport protocol itself. Additionally, remove
a TODO to avoid the use of channel buffering for message queues in http
transports; instead, always write to message buffers in a select
statement containing a read from the done channel. The bounded size of
message buffers then serves to create backpressure for an overloaded
server.
Change-Id: I5701c5b95a5ae73d796a634e434f41dfcdbddf51
Reviewed-on: https://go-review.googlesource.com/c/tools/+/668237
Reviewed-by: Jonathan Amsterdam <jba@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Robert Findley <rfindley@google.com>
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
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Alan Donovan <adonovan@google.com>
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
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
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>
Commit-Queue: Robert Findley <rfindley@google.com>
Auto-Submit: Robert Findley <rfindley@google.com>
TryBot-Bypass: Robert Findley <rfindley@google.com>
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
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
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>
This CL contains an minimal prototype of an MCP SDK, using the
"new" jsonrpc2_v2 package (similar to x/exp/jsonrpc2).
Much is still yet to do, but this initial version addressed the
following aspects:
- Support for newline delimited JSONRPC2 framing, and message logging.
- A generated protocol package, containing type definitions to be used
in transport.
- A minimal jsonschema package to be used for both reading the MCP spec,
and for serving Tool input schemas.
- A transport abstraction, and two transport implementations: stdio, and
local (for testing).
- Client and Server types, to be configured with features and then
connected using their Connect methods, which return (respectively) a
ServerConnection and ClientConnection object.
- A minimal binding API for tools.
A catalog of things not yet done is in doc.go, but we should review this
CL eagerly, as it contains the fundamental building blocks of an
eventual SDK.
It is the intention that this package is more-or-less standalone, as it
may eventually be carved out into a separate repository. As such, its
only dependency within x/tools is jsonrpc2_v2, and the only change
required to that package is to expose a callback when the connection is
closed.
Change-Id: Ib66018961014f85a8884d56ab721d5642c98443c
Reviewed-on: https://go-review.googlesource.com/c/tools/+/667036
Reviewed-by: Jonathan Amsterdam <jba@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
