refactor(eve): move local tracing out of the harness into src/tracing

.changeset/tracing-module-move.md

@@ -0,0 +1,5 @@
+---
+"eve": patch
+---
+
+The local tracing subsystem (spool writer/reader, retention, the zero-config local OTel runtime, and agent span capture) moved from `src/harness` into its own `src/tracing` module; no behavior change.

packages/eve/src/cli/commands/trace.integration.test.ts

@@ -4,7 +4,7 @@ import { join } from "node:path";
 
 import { afterEach, describe, expect, it } from "vitest";
 
-import { listLocalTraces } from "#harness/local-trace-reader.js";
+import { listLocalTraces } from "#tracing/local-trace-reader.js";
 
 import { resolveLocalTraces, runTraceListCommand, runTraceShowCommand } from "./trace.js";
 

packages/eve/src/cli/commands/trace.ts

@@ -2,12 +2,12 @@ import { basename } from "node:path";
 
 import { formatElapsed } from "#cli/format-elapsed.js";
 import { createCliTheme, renderCliSection, sanitizeForTerminal } from "#cli/ui/output.js";
-import type { LocalTrace, LocalTraceSpan } from "#harness/local-trace-reader.js";
+import type { LocalTrace, LocalTraceSpan } from "#tracing/local-trace-reader.js";
 import {
   compareLocalTraceSpans,
   describeLocalTraceSpan,
   listLocalTraces,
-} from "#harness/local-trace-reader.js";
+} from "#tracing/local-trace-reader.js";
 
 const TRACE_DISPLAY_DIRECTORY = ".eve/traces/v1";
 

packages/eve/src/cli/dev/tui/traces/trace-conversation.test.ts

@@ -1,7 +1,7 @@
 import { describe, expect, it } from "vitest";
 
 import { stripAnsi, visibleLength } from "#cli/ui/terminal-text.js";
-import type { LocalTrace, LocalTraceSpan } from "#harness/local-trace-reader.js";
+import type { LocalTrace, LocalTraceSpan } from "#tracing/local-trace-reader.js";
 
 import { createTheme } from "../theme.js";
 import { buildConversationItems, renderConversationItem } from "./trace-conversation.js";

packages/eve/src/cli/dev/tui/traces/trace-conversation.ts

@@ -14,8 +14,8 @@ import {
   visibleLength,
   wrapVisibleLine,
 } from "#cli/ui/terminal-text.js";
-import type { LocalTrace, LocalTraceSpan } from "#harness/local-trace-reader.js";
-import { compareLocalTraceSpans } from "#harness/local-trace-reader.js";
+import type { LocalTrace, LocalTraceSpan } from "#tracing/local-trace-reader.js";
+import { compareLocalTraceSpans } from "#tracing/local-trace-reader.js";
 
 import { formatCompactTokenCount } from "../stream-format.js";
 import type { Theme } from "../theme.js";

packages/eve/src/cli/dev/tui/traces/trace-store.ts

@@ -10,12 +10,12 @@
 import { readdir, readFile, stat } from "node:fs/promises";
 import { join } from "node:path";
 
-import type { LocalTrace, LocalTraceSpan } from "#harness/local-trace-reader.js";
-import { assembleLocalTrace, parseLocalTraceSegment } from "#harness/local-trace-reader.js";
+import type { LocalTrace, LocalTraceSpan } from "#tracing/local-trace-reader.js";
+import { assembleLocalTrace, parseLocalTraceSegment } from "#tracing/local-trace-reader.js";
 import {
   resolveLocalTraceSchemaDirectory,
   resolveLocalTraceSegmentsDirectory,
-} from "#harness/local-trace-span-processor.js";
+} from "#tracing/local-trace-span-processor.js";
 
 const TRACE_ID_PATTERN = /^[0-9a-f]{32}$/u;
 const SPAN_FILE_PATTERN = /^[0-9a-f]{16}\.otlp\.json$/u;

packages/eve/src/cli/dev/tui/traces/trace-view.test.ts

@@ -1,7 +1,7 @@
 import { describe, expect, it } from "vitest";
 
 import { stripAnsi, visibleLength } from "#cli/ui/terminal-text.js";
-import type { LocalTrace, LocalTraceSpan } from "#harness/local-trace-reader.js";
+import type { LocalTrace, LocalTraceSpan } from "#tracing/local-trace-reader.js";
 
 import { createTheme } from "../theme.js";
 import {

packages/eve/src/cli/dev/tui/traces/trace-view.ts

@@ -15,8 +15,8 @@ import {
   visibleLength,
   wrapVisibleLine,
 } from "#cli/ui/terminal-text.js";
-import type { LocalTraceSpan } from "#harness/local-trace-reader.js";
-import { describeLocalTraceSpan } from "#harness/local-trace-reader.js";
+import type { LocalTraceSpan } from "#tracing/local-trace-reader.js";
+import { describeLocalTraceSpan } from "#tracing/local-trace-reader.js";
 
 import type { Theme } from "../theme.js";
 import { formatAttributeContent } from "./trace-content.js";

packages/eve/src/cli/dev/tui/traces/trace-viewer-session.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it, vi } from "vitest";
 
-import type { LocalTrace, LocalTraceSpan } from "#harness/local-trace-reader.js";
+import type { LocalTrace, LocalTraceSpan } from "#tracing/local-trace-reader.js";
 
 import { createTheme } from "../theme.js";
 import type { TraceStore } from "./trace-store.js";

packages/eve/src/cli/dev/tui/traces/trace-viewer-state.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from "vitest";
 
-import type { LocalTrace, LocalTraceSpan } from "#harness/local-trace-reader.js";
+import type { LocalTrace, LocalTraceSpan } from "#tracing/local-trace-reader.js";
 
 import type { TraceStoreEntry } from "./trace-store.js";
 import type { TerminalKey } from "../stream-format.js";

packages/eve/src/cli/dev/tui/traces/trace-viewer-state.ts

@@ -7,7 +7,7 @@
  * viewer without losing the user's selection.
  */
 
-import type { LocalTrace, LocalTraceSpan } from "#harness/local-trace-reader.js";
+import type { LocalTrace, LocalTraceSpan } from "#tracing/local-trace-reader.js";
 
 import type { ConversationItem } from "#cli/dev/tui/traces/trace-conversation.js";
 import {

packages/eve/src/execution/dispatch-runtime-actions-step.ts

@@ -46,7 +46,7 @@ import { buildSubagentRunInput, type SubagentInputSource } from "#execution/suba
 import { createWorkflowRuntime, workflowEntryReference } from "#execution/workflow-runtime.js";
 import { createLogger, logError } from "#internal/logging.js";
 import { toErrorMessage } from "#shared/errors.js";
-import { readSessionTraceContext } from "#harness/agent-trace-context-store.js";
+import { readSessionTraceContext } from "#tracing/agent-trace-context-store.js";
 import { resolveSubagentDepth } from "#harness/subagent-depth.js";
 
 const log = createLogger("execution.dispatch-runtime-actions");

packages/eve/src/execution/workflow-steps.ts

@@ -19,7 +19,7 @@ import { BundleKey, ChannelKey } from "#runtime/sessions/runtime-context-keys.js
 import { runStep } from "#context/run-step.js";
 import { deserializeContext, serializeContext } from "#context/serialize.js";
 import { getHarnessEmissionState } from "#harness/emission.js";
-import { preserveSerializedAgentTraceState } from "#harness/agent-trace-context-store.js";
+import { preserveSerializedAgentTraceState } from "#tracing/agent-trace-context-store.js";
 import { readTurnSleepDurationMs } from "#harness/turn-sleep.js";
 import { isTurnCancellation, throwIfTurnAborted } from "#harness/turn-cancellation.js";
 import { setChannelContext } from "#execution/channel-context.js";

packages/eve/src/internal/nitro/host/local-tracing-runtime-plugin.ts

@@ -1,6 +1,6 @@
 import { basename } from "node:path";
 
-import { installLocalInstrumentationRuntime } from "#harness/local-instrumentation-runtime.js";
+import { installLocalInstrumentationRuntime } from "#tracing/local-instrumentation-runtime.js";
 import { resolveInstalledPackageInfo } from "#internal/application/package.js";
 import { DEVELOPMENT_WORKER_APP_ROOT_ENV } from "#internal/workflow/development-world-protocol.js";
 

packages/eve/src/harness/agent-otel-content.test.ts → packages/eve/src/tracing/agent-otel-content.test.ts

@@ -3,7 +3,7 @@ import { describe, expect, it } from "vitest";
 import {
   CONTENT_ATTRIBUTE_LIMIT,
   toolResultsContentAttribute,
-} from "#harness/agent-otel-content.js";
+} from "#tracing/agent-otel-content.js";
 
 describe("toolResultsContentAttribute", () => {
   it("returns the full payload when it fits", () => {

packages/eve/src/harness/agent-otel-provider.test.ts → packages/eve/src/tracing/agent-otel-provider.test.ts

@@ -12,7 +12,7 @@ import {
   createAgentOtelInstrumentation,
   InMemoryAgentTraceStateStore,
   SESSION_WINDOW_TURN_LIMIT,
-} from "#harness/agent-otel-provider.js";
+} from "#tracing/agent-otel-provider.js";
 import {
   createInstrumentationHooks,
   type InstrumentationAttemptScope,

packages/eve/src/harness/agent-otel-provider.ts → packages/eve/src/tracing/agent-otel-provider.ts

@@ -15,7 +15,7 @@ import {
   systemPromptAttribute,
   textContentAttribute,
   toolResultsContentAttribute,
-} from "#harness/agent-otel-content.js";
+} from "#tracing/agent-otel-content.js";
 import type {
   InstrumentationAttemptMetadataEvent,
   InstrumentationAttemptScope,

packages/eve/src/harness/agent-trace-context-store.test.ts → packages/eve/src/tracing/agent-trace-context-store.test.ts

@@ -6,7 +6,7 @@ import {
   ContextAgentTraceStateStore,
   preserveSerializedAgentTraceState,
   readSessionTraceContext,
-} from "#harness/agent-trace-context-store.js";
+} from "#tracing/agent-trace-context-store.js";
 
 describe("ContextAgentTraceStateStore", () => {
   it("restores serializable session and turn context", async () => {

packages/eve/src/harness/agent-trace-context-store.ts → packages/eve/src/tracing/agent-trace-context-store.ts

@@ -6,7 +6,7 @@ import type {
   AgentSessionTraceState,
   AgentTraceStateStore,
   AgentTurnTraceState,
-} from "#harness/agent-otel-provider.js";
+} from "#tracing/agent-otel-provider.js";
 
 interface AgentTraceContextState {
   readonly sessions: Readonly<Record<string, AgentSessionTraceState>>;

packages/eve/src/harness/agent-trace-span-processor.test.ts → packages/eve/src/tracing/agent-trace-span-processor.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it, vi } from "vitest";
 
-import { AgentTraceSpanProcessor } from "#harness/agent-trace-span-processor.js";
+import { AgentTraceSpanProcessor } from "#tracing/agent-trace-span-processor.js";
 
 describe("AgentTraceSpanProcessor", () => {
   it("routes an agent trace and releases it at session terminal", () => {

packages/eve/src/harness/local-instrumentation-runtime-conflict.scenario.test.ts → packages/eve/src/tracing/local-instrumentation-runtime-conflict.scenario.test.ts

@@ -6,7 +6,7 @@ import { trace } from "@opentelemetry/api";
 import { BasicTracerProvider } from "@opentelemetry/sdk-trace-base";
 import { afterEach, describe, expect, it } from "vitest";
 
-import { installLocalInstrumentationRuntime } from "#harness/local-instrumentation-runtime.js";
+import { installLocalInstrumentationRuntime } from "#tracing/local-instrumentation-runtime.js";
 
 let appRoot: string | undefined;
 

packages/eve/src/harness/local-instrumentation-runtime.scenario.test.ts → packages/eve/src/tracing/local-instrumentation-runtime.scenario.test.ts

@@ -8,10 +8,10 @@ import { afterEach, describe, expect, it } from "vitest";
 
 import { ContextContainer, contextStorage } from "#context/container.js";
 import { createAiSdkHookBridge } from "#harness/ai-sdk-hook-bridge.js";
-import { listLocalTraces } from "#harness/local-trace-reader.js";
+import { listLocalTraces } from "#tracing/local-trace-reader.js";
 import type { InstrumentationAttemptScope } from "#harness/instrumentation-lifecycle.js";
-import { installLocalInstrumentationRuntime } from "#harness/local-instrumentation-runtime.js";
-import { LocalTraceSpanProcessor } from "#harness/local-trace-span-processor.js";
+import { installLocalInstrumentationRuntime } from "#tracing/local-instrumentation-runtime.js";
+import { LocalTraceSpanProcessor } from "#tracing/local-trace-span-processor.js";
 
 const temporaryDirectories: string[] = [];
 

packages/eve/src/harness/local-instrumentation-runtime.ts → packages/eve/src/tracing/local-instrumentation-runtime.ts

@@ -1,9 +1,9 @@
 import { context, trace } from "#compiled/@opentelemetry/api/index.js";
 import { registerOTel } from "#compiled/@vercel/otel/index.js";
 
-import { ContextAgentTraceStateStore } from "#harness/agent-trace-context-store.js";
-import { createAgentOtelInstrumentation } from "#harness/agent-otel-provider.js";
-import { AgentTraceSpanProcessor } from "#harness/agent-trace-span-processor.js";
+import { ContextAgentTraceStateStore } from "#tracing/agent-trace-context-store.js";
+import { createAgentOtelInstrumentation } from "#tracing/agent-otel-provider.js";
+import { AgentTraceSpanProcessor } from "#tracing/agent-trace-span-processor.js";
 import {
   createInstrumentationHooks,
   type InstrumentationProviderDefinition,
@@ -16,8 +16,8 @@ import {
 import {
   requestLocalTraceStorePrune,
   resolveLocalTraceRetentionSettings,
-} from "#harness/local-trace-retention.js";
-import { LocalTraceSpanProcessor } from "#harness/local-trace-span-processor.js";
+} from "#tracing/local-trace-retention.js";
+import { LocalTraceSpanProcessor } from "#tracing/local-trace-span-processor.js";
 
 /** Installs the zero-config local OTel runtime once in an `eve dev` worker. */
 export function installLocalInstrumentationRuntime(input: {

packages/eve/src/harness/local-trace-reader.ts → packages/eve/src/tracing/local-trace-reader.ts

@@ -11,7 +11,7 @@
 import { readdir, readFile, stat } from "node:fs/promises";
 import { join } from "node:path";
 
-import { resolveLocalTraceSchemaDirectory } from "#harness/local-trace-span-processor.js";
+import { resolveLocalTraceSchemaDirectory } from "#tracing/local-trace-span-processor.js";
 
 const TRACE_ID_PATTERN = /^[0-9a-f]{32}$/u;
 const SPAN_FILE_PATTERN = /^([0-9a-f]{16})\.otlp\.json$/u;

packages/eve/src/harness/local-trace-retention.integration.test.ts → packages/eve/src/tracing/local-trace-retention.integration.test.ts

@@ -3,11 +3,11 @@ import { join } from "node:path";
 
 import { describe, expect, it } from "vitest";
 
-import { pruneLocalTraceStore } from "#harness/local-trace-retention.js";
+import { pruneLocalTraceStore } from "#tracing/local-trace-retention.js";
 import {
   resolveLocalTraceSchemaDirectory,
   resolveLocalTraceSegmentsDirectory,
-} from "#harness/local-trace-span-processor.js";
+} from "#tracing/local-trace-span-processor.js";
 import { useTemporaryDirectories } from "#internal/testing/use-temporary-app-roots.js";
 
 const createScratchDirectory = useTemporaryDirectories();

packages/eve/src/harness/local-trace-retention.test.ts → packages/eve/src/tracing/local-trace-retention.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from "vitest";
 
-import { resolveLocalTraceRetentionSettings } from "#harness/local-trace-retention.js";
+import { resolveLocalTraceRetentionSettings } from "#tracing/local-trace-retention.js";
 
 const SEVEN_DAYS_MS = 7 * 24 * 60 * 60 * 1_000;
 const FIVE_HUNDRED_TWELVE_MIB = 512 * 1024 * 1024;

packages/eve/src/harness/local-trace-retention.ts → packages/eve/src/tracing/local-trace-retention.ts

@@ -5,7 +5,7 @@ import { join } from "node:path";
 import {
   resolveLocalTraceSchemaDirectory,
   resolveLocalTraceSegmentsDirectory,
-} from "#harness/local-trace-span-processor.js";
+} from "#tracing/local-trace-span-processor.js";
 import { createLogger, formatError } from "#internal/logging.js";
 
 const log = createLogger("harness.local-trace-retention");

scripts/guard-invariants.mjs

@@ -16,10 +16,10 @@
  *   rule 13 — No spread-ternary object composition
  *             (`...(c ? {} : { k: v })`). (Rationale: hard to read, easy
  *             to mistype; declare the object then assign optional keys.)
- *   rule 15 — No `@workflow/*` imports inside `src/channel/**` or
- *             `src/harness/**`. Channels and harnesses must stay
- *             workflow-agnostic — only runtime/execution code touches
- *             workflow primitives.
+ *   rule 15 — No `@workflow/*` imports inside `src/channel/**`,
+ *             `src/harness/**`, or `src/tracing/**`. Channels, harnesses,
+ *             and tracing must stay workflow-agnostic — only
+ *             runtime/execution code touches workflow primitives.
  *   rule 19 — No `new AsyncLocalStorage()` outside the two allowlisted
  *             files. All ambient runtime state flows through a single
  *             `EveContext`.
@@ -240,7 +240,9 @@ const WORKFLOW_IMPORT_RE = /from ["']@workflow\b/;
  */
 function isChannelOrHarness(posix) {
   return (
-    posix.startsWith("packages/eve/src/channel/") || posix.startsWith("packages/eve/src/harness/")
+    posix.startsWith("packages/eve/src/channel/") ||
+    posix.startsWith("packages/eve/src/harness/") ||
+    posix.startsWith("packages/eve/src/tracing/")
   );
 }
 
@@ -257,7 +259,7 @@ function checkRule15(posix, lines, violations) {
         rule: 15,
         file: posix,
         line: idx + 1,
-        message: `imports from "@workflow/*". Channel and harness code must stay workflow-agnostic. Move the workflow primitive call into src/runtime/ or src/execution/ and have the channel/harness call a thin runtime helper instead.`,
+        message: `imports from "@workflow/*". Channel, harness, and tracing code must stay workflow-agnostic. Move the workflow primitive call into src/runtime/ or src/execution/ and have the caller use a thin runtime helper instead.`,
       });
     }
   });