Co-authored-by: Matt <77928207+mattzcarey@users.noreply.github.com> Co-authored-by: Konstantin Konstantinov <KKonstantinov@users.noreply.github.com> Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
52 lines
2.3 KiB
TypeScript
52 lines
2.3 KiB
TypeScript
/**
|
|
* Advertises the sampling capability, registers a `sampling/createMessage`
|
|
* handler that returns a canned summary, then calls the `summarize` tool and
|
|
* asserts the canned text round-tripped.
|
|
*
|
|
* The same handler serves both protocol eras: on the 2025-era leg
|
|
* (`--legacy`) the server pushes `sampling/createMessage` and this handler
|
|
* answers it directly; on the 2026-07-28 leg the auto-fulfilment driver
|
|
* dispatches the embedded `sampling/createMessage` from the server's
|
|
* `inputRequired` result to this same handler, then retries the tool call
|
|
* with the response attached.
|
|
*/
|
|
import { check, parseExampleArgs, siblingPath } from '@mcp-examples/shared';
|
|
import { Client, StreamableHTTPClientTransport } from '@modelcontextprotocol/client';
|
|
import { StdioClientTransport } from '@modelcontextprotocol/client/stdio';
|
|
|
|
const { transport, url, era } = parseExampleArgs();
|
|
|
|
const client = new Client(
|
|
{ name: 'sampling-example-client', version: '1.0.0' },
|
|
{
|
|
versionNegotiation: { mode: era === 'modern' ? 'auto' : 'legacy' },
|
|
capabilities: { sampling: {} }
|
|
}
|
|
);
|
|
|
|
await (transport === 'stdio'
|
|
? client.connect(new StdioClientTransport({ command: 'npx', args: ['-y', 'tsx', siblingPath(import.meta.url, 'server.ts')] }))
|
|
: client.connect(new StreamableHTTPClientTransport(new URL(url))));
|
|
|
|
client.setRequestHandler('sampling/createMessage', async () => ({
|
|
role: 'assistant',
|
|
content: { type: 'text', text: '[canned summary]' },
|
|
model: 'stub',
|
|
stopReason: 'endTurn'
|
|
}));
|
|
|
|
if (transport === 'http' && era === 'legacy') {
|
|
// Push-style `ctx.mcpReq.requestSampling` needs a sessionful return
|
|
// path: the client's response to `sampling/createMessage` is a separate
|
|
// POST that must reach the SAME server instance that sent the request.
|
|
// `createMcpHandler`'s default stateless-legacy posture has no such
|
|
// path — see `../legacy-routing/` for the sessionful `isLegacyRequest`
|
|
// composition. The push-style flow is exercised on stdio/legacy; this
|
|
// leg only verifies the 2025 `initialize` handshake succeeded.
|
|
check.ok(client.getServerCapabilities()?.tools);
|
|
} else {
|
|
const result = await client.callTool({ name: 'summarize', arguments: { text: 'hello world' } });
|
|
check.equal(result.content?.[0]?.type === 'text' ? result.content[0].text : '', '[canned summary]');
|
|
}
|
|
|
|
await client.close();
|