Skip to content

test(e2e): Port cloudflare-mcp-agent to span streaming #23859

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
JPeer264 merged 1 commit into from
Sep 2, 2026
+23 −33
Merged

test(e2e): Port cloudflare-mcp-agent to span streaming #23859

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 0 additions & 2 deletions dev-packages/e2e-tests/test-applications/cloudflare-mcp-agent/src/index.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -50,7 +50,6 @@ class MyMCPAgentBase extends McpAgent<Env, unknown, Record<string, unknown>> {

export const MyMCPAgent = Sentry.instrumentDurableObjectWithSentry(
(env: Env) => ({
traceLifecycle: 'static',
dsn: env.E2E_TEST_DSN,
environment: 'qa',
tunnel: `http://localhost:3031/`,
Expand All @@ -71,7 +70,6 @@ export const MyMCPAgent = Sentry.instrumentDurableObjectWithSentry(

export default Sentry.withSentry(
(env: Env) => ({
traceLifecycle: 'static',
dsn: env.E2E_TEST_DSN,
environment: 'qa',
tunnel: `http://localhost:3031/`,
Expand Down
54 changes: 23 additions & 31 deletions dev-packages/e2e-tests/test-applications/cloudflare-mcp-agent/tests/index.test.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,16 +1,9 @@
import { expect, test } from '@playwright/test';
import { waitForRequest } from '@sentry-internal/test-utils';
import { waitForStreamedSpan } from '@sentry-internal/test-utils';

test('sends spans for MCP tool calls via MCPAgent (DurableObject)', async ({ baseURL }) => {
const privateMessage = 'cloudflare-agent-private-capture-policy-message';
const mcpToolWaiter = waitForRequest('cloudflare-mcp-agent', event => {
const transaction = event.envelope[1][0][1];
return (
typeof transaction !== 'string' &&
'transaction' in transaction &&
transaction.transaction === 'tools/call my-tool'
);
});
const mcpSpanPromise = waitForStreamedSpan('cloudflare-mcp-agent', span => span.name === 'tools/call my-tool');

// Step 1: Initialize the MCP session
const initResponse = await fetch(`${baseURL}/mcp`, {
Expand Down Expand Up @@ -76,30 +69,29 @@ test('sends spans for MCP tool calls via MCPAgent (DurableObject)', async ({ bas
expect(response.status).toBe(200);
await expect(response.text()).resolves.toContain(`Tool my-tool: ${privateMessage}`);

const mcpData = await mcpToolWaiter;
const mcpEvent = mcpData.envelope[1][0][1];
const traceData = mcpEvent.contexts?.trace?.data;
const mcpSpan = await mcpSpanPromise;

expect(mcpEvent.contexts?.trace?.trace_id).toBe(mcpData.envelope[0].trace.trace_id);
expect(mcpEvent.contexts?.trace).toEqual({
trace_id: expect.any(String),
parent_span_id: expect.any(String),
span_id: expect.any(String),
op: 'mcp.server',
origin: 'auto.function.mcp_server',
expect(mcpSpan).toEqual({
trace_id: expect.stringMatching(/^[a-f0-9]{32}$/),
parent_span_id: expect.stringMatching(/^[a-f0-9]{16}$/),
span_id: expect.stringMatching(/^[a-f0-9]{16}$/),
name: 'tools/call my-tool',
start_timestamp: expect.any(Number),
end_timestamp: expect.any(Number),
status: 'ok',
data: expect.objectContaining({
'sentry.origin': 'auto.function.mcp_server',
'sentry.op': 'mcp.server',
'mcp.method.name': 'tools/call',
'mcp.tool.name': 'my-tool',
'mcp.tool.extra': 'from-mcpagent',
'mcp.tool.result.content_count': 1,
'mcp.tool.result.content_type': 'text',
is_segment: true,
attributes: expect.objectContaining({
'sentry.origin': { value: 'auto.function.mcp_server', type: 'string' },
'sentry.op': { value: 'mcp.server', type: 'string' },
'mcp.method.name': { value: 'tools/call', type: 'string' },
'mcp.tool.name': { value: 'my-tool', type: 'string' },
'mcp.tool.extra': { value: 'from-mcpagent', type: 'string' },
'mcp.tool.result.content_count': { value: 1, type: 'integer' },
'mcp.tool.result.content_type': { value: 'text', type: 'string' },
}),
Comment on lines 81 to 91

@sentry sentry Bot Sep 2, 2026

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Bug: The test's strict toEqual assertion is brittle as it doesn't account for the optional links field, causing it to fail if links are added to spans in the future.
Severity: LOW

Suggested Fix

To make the test more robust against future changes, use expect.objectContaining instead of toEqual. This will ensure the test only validates the presence and values of the specified fields, and will not fail if other optional fields like links are added to the span in the future.

Prompt for AI Agent 
Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location:
dev-packages/e2e-tests/test-applications/cloudflare-mcp-agent/tests/index.test.ts#L74-L91

Potential issue: The test uses a strict `toEqual` assertion that does not account for
the optional `links` field in the `SerializedStreamedSpan` type. While the test
currently passes because the MCP instrumentation does not add links to spans, it is
brittle. This test relies on the implicit assumption that `links` will never be
populated. If future changes to the MCP instrumentation add span links, which is a valid
use case, this test will unexpectedly fail, creating future maintenance overhead.

Did we get this right? 👍 / 👎 to inform future reviews.

});
expect(traceData?.['mcp.request.argument.message']).toBeUndefined();
expect(traceData?.['mcp.tool.result.content']).toBeUndefined();
expect(traceData?.['mcp.tool.input']).toBeUndefined();
expect(JSON.stringify(traceData)).not.toContain(privateMessage);
expect(mcpSpan.attributes['mcp.request.argument.message']).toBeUndefined();
expect(mcpSpan.attributes['mcp.tool.result.content']).toBeUndefined();
expect(mcpSpan.attributes['mcp.tool.input']).toBeUndefined();
expect(JSON.stringify(mcpSpan.attributes)).not.toContain(privateMessage);
});
Loading