feat(core): add mcp support (#34513)

packages/core/test/config/config.test.ts

@@ -76,6 +76,18 @@ describe("Config", () => {
     }),
   )
 
+  it.effect("detects a bare v1-shaped mcp block while leaving v2 mcp config alone", () =>
+    Effect.sync(() => {
+      // V1 lists servers directly under `mcp`, so a file with only `$schema` + `mcp` still migrates.
+      expect(ConfigMigrateV1.isV1({ mcp: { context7: { type: "local", command: ["npx"] } } })).toBe(true)
+      expect(ConfigMigrateV1.isV1({ $schema: "x", mcp: { executor: { type: "remote", url: "https://x" } } })).toBe(true)
+      // V2 nests under `mcp.servers`, so it must not be misdetected and re-migrated.
+      expect(ConfigMigrateV1.isV1({ mcp: { servers: { context7: { type: "local", command: ["npx"] } } } })).toBe(false)
+      expect(ConfigMigrateV1.isV1({ mcp: {} })).toBe(false)
+      expect(ConfigMigrateV1.isV1({ mcp: { timeout: { request: 1000 } } })).toBe(false)
+    }),
+  )
+
   it.effect("migrates arbitrary v1 configuration into valid v2 configuration", () =>
     Effect.sync(() => {
       FastCheck.assert(

packages/core/test/session-runner-recorded.test.ts

@@ -30,6 +30,7 @@ import { SystemContextRegistry } from "@opencode-ai/core/system-context/registry
 import { SystemContext } from "@opencode-ai/core/system-context"
 import { SkillGuidance } from "@opencode-ai/core/skill/guidance"
 import { ReferenceGuidance } from "@opencode-ai/core/reference/guidance"
+import { McpGuidance } from "@opencode-ai/core/mcp/guidance"
 import { describe, expect } from "bun:test"
 import { eq } from "drizzle-orm"
 import { Effect, Layer } from "effect"
@@ -72,6 +73,7 @@ const systemContext = SystemContextRegistry.layer
 const location = Location.layer({ directory: AbsolutePath.make("/project") }).pipe(Layer.provide(Project.defaultLayer))
 const skillGuidance = Layer.mock(SkillGuidance.Service, { load: () => Effect.succeed(SystemContext.empty) })
 const referenceGuidance = Layer.mock(ReferenceGuidance.Service, { load: () => Effect.succeed(SystemContext.empty) })
+const mcpGuidance = Layer.mock(McpGuidance.Service, { load: () => Effect.succeed(SystemContext.empty) })
 const config = Layer.succeed(Config.Service, Config.Service.of({ entries: () => Effect.succeed([]) }))
 const runner = SessionRunnerLLM.defaultLayer.pipe(
   Layer.provide(SessionCompaction.layer),
@@ -87,6 +89,7 @@ const runner = SessionRunnerLLM.defaultLayer.pipe(
   Layer.provide(agents),
   Layer.provide(skillGuidance),
   Layer.provide(referenceGuidance),
+  Layer.provide(mcpGuidance),
   Layer.provide(config),
 )
 const execution = Layer.effect(

packages/core/test/session-runner.test.ts

@@ -52,6 +52,7 @@ import { SystemContext } from "@opencode-ai/core/system-context"
 import { SystemContextRegistry } from "@opencode-ai/core/system-context/registry"
 import { SkillGuidance } from "@opencode-ai/core/skill/guidance"
 import { ReferenceGuidance } from "@opencode-ai/core/reference/guidance"
+import { McpGuidance } from "@opencode-ai/core/mcp/guidance"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { Location } from "@opencode-ai/core/location"
 import { ProviderV2 } from "@opencode-ai/core/provider"
@@ -217,6 +218,7 @@ const skillGuidance = Layer.mock(SkillGuidance.Service, {
     ),
 })
 const referenceGuidance = Layer.mock(ReferenceGuidance.Service, { load: () => Effect.succeed(SystemContext.empty) })
+const mcpGuidance = Layer.mock(McpGuidance.Service, { load: () => Effect.succeed(SystemContext.empty) })
 const config = Layer.succeed(
   Config.Service,
   Config.Service.of({
@@ -248,6 +250,7 @@ const runner = SessionRunnerLLM.layer.pipe(
   Layer.provide(agents),
   Layer.provide(skillGuidance),
   Layer.provide(referenceGuidance),
+  Layer.provide(mcpGuidance),
   Layer.provide(config),
 )
 const execution = Layer.effect(