diff --git a/packages/opencode/src/session/session.ts b/packages/opencode/src/session/session.ts
index a2a91cd47b5e..1ae5b7f0b311 100644
--- a/packages/opencode/src/session/session.ts
+++ b/packages/opencode/src/session/session.ts
@@ -32,6 +32,7 @@ import { MessageV2 } from "./message-v2"
 import type { InstanceContext } from "../project/instance-context"
 import { InstanceState } from "@/effect/instance-state"
 import { Snapshot } from "@/snapshot"
+import { Project } from "@/project/project"
 import { ProjectV2 } from "@opencode-ai/core/project"
 import { WorkspaceV2 } from "@opencode-ai/core/workspace"
 import { SessionID, MessageID, PartID } from "./schema"
@@ -486,7 +487,7 @@ export type Patch = Omit<Partial<Info>, "time" | "share" | "summary" | "revert"
 const layer: Layer.Layer<
   Service,
   never,
-  BackgroundJob.Service | RuntimeFlags.Service | Database.Service | EventV2Bridge.Service
+  BackgroundJob.Service | RuntimeFlags.Service | Database.Service | EventV2Bridge.Service | Project.Service
 > = Layer.effect(
   Service,
   Effect.gen(function* () {
@@ -495,6 +496,7 @@ const layer: Layer.Layer<
     const background = yield* BackgroundJob.Service
     const events = yield* EventV2Bridge.Service
     const flags = yield* RuntimeFlags.Service
+    const projects = yield* Project.Service
 
     const createNext = Effect.fn("Session.createNext")(function* (input: {
       id?: SessionID
@@ -509,11 +511,25 @@ const layer: Layer.Layer<
       permission?: PermissionV1.Ruleset
     }) {
       const ctx = yield* InstanceState.context
+      // The instance context caches the project id resolved when the instance
+      // was loaded. Another opencode process can rekey the project (a git
+      // remote change migrates the row and deletes the previous one), leaving
+      // this process with a deleted project id. Verify the row still exists and
+      // re-resolve the directory when it does not, so a new session can never
+      // reference a missing project.
+      const projectID = (yield* db
+        .select({ id: ProjectTable.id })
+        .from(ProjectTable)
+        .where(eq(ProjectTable.id, ctx.project.id))
+        .get()
+        .pipe(Effect.orDie))
+        ? ctx.project.id
+        : (yield* projects.fromDirectory(input.directory)).project.id
       const result: Info = {
         id: SessionID.descending(input.id),
         slug: Slug.create(),
         version: InstallationVersion,
-        projectID: ctx.project.id,
+        projectID,
         directory: input.directory,
         path: input.path,
         workspaceID: input.workspaceID,
@@ -1010,7 +1026,7 @@ function listByProject(
 export const node = LayerNode.make({
   service: Service,
   layer: layer,
-  deps: [BackgroundJob.node, RuntimeFlags.node, Database.node, EventV2Bridge.node],
+  deps: [BackgroundJob.node, RuntimeFlags.node, Database.node, EventV2Bridge.node, Project.node],
 })
 
 export * as Session from "./session"
diff --git a/packages/opencode/test/session/session.test.ts b/packages/opencode/test/session/session.test.ts
index c4301d20401c..3cd2cb01052f 100644
--- a/packages/opencode/test/session/session.test.ts
+++ b/packages/opencode/test/session/session.test.ts
@@ -1,4 +1,5 @@
 import { describe, expect } from "bun:test"
+import { $ } from "bun"
 import { SessionV1 } from "@opencode-ai/core/v1/session"
 import { EventV2 } from "@opencode-ai/core/event"
 import { SessionProjector } from "@opencode-ai/core/session/projector"
@@ -7,7 +8,7 @@ import { Session as SessionNs } from "@/session/session"
 import { MessageV2 } from "../../src/session/message-v2"
 import { MessageID, PartID, type SessionID } from "../../src/session/schema"
 import { CrossSpawnSpawner } from "@opencode-ai/core/cross-spawn-spawner"
-import { provideInstance, tmpdirScoped } from "../fixture/fixture"
+import { provideInstance, TestInstance, tmpdirScoped } from "../fixture/fixture"
 import { testEffect } from "../lib/effect"
 import { RuntimeFlags } from "@/effect/runtime-flags"
 import { EventV2Bridge } from "@/event-v2-bridge"
@@ -16,6 +17,7 @@ import { AppNodeBuilder } from "@opencode-ai/core/effect/app-node-builder"
 import { LayerNode } from "@opencode-ai/core/effect/layer-node"
 import { InstanceStore } from "@/project/instance-store"
 import { InstanceBootstrap } from "@/project/bootstrap"
+import { Project } from "@/project/project"
 
 const it = testEffect(
   AppNodeBuilder.build(
@@ -25,6 +27,7 @@ const it = testEffect(
       SessionProjector.node,
       CrossSpawnSpawner.node,
       InstanceStore.node,
+      Project.node,
     ]),
     [
       [RuntimeFlags.node, RuntimeFlags.layer({ experimentalWorkspaces: false })],
@@ -283,3 +286,35 @@ describe("Session", () => {
     }),
   )
 })
+
+describe("Session.create with a stale project id", () => {
+  it.instance(
+    "uses the current project when the cached project row was deleted",
+    () =>
+      Effect.gen(function* () {
+        const session = yield* SessionNs.Service
+        const project = yield* Project.Service
+        const instance = yield* TestInstance
+        const created = yield* Effect.acquireRelease(session.create({ title: "before-rekey" }), (info) =>
+          session.remove(info.id).pipe(Effect.ignore),
+        )
+
+        // Rekey the project the way another opencode process would: adding a
+        // remote changes the resolved id and fromDirectory migrates the row,
+        // deleting the id this instance still holds.
+        yield* Effect.promise(() =>
+          $`git remote add origin git@github.com:opencode-test/stale-project-id.git`.cwd(instance.directory).quiet(),
+        )
+        const migrated = yield* project.fromDirectory(instance.directory)
+        expect(migrated.project.id).not.toBe(created.projectID)
+
+        const after = yield* Effect.acquireRelease(session.create({ title: "after-rekey" }), (info) =>
+          session.remove(info.id).pipe(Effect.ignore),
+        )
+
+        expect(after.projectID).toBe(migrated.project.id)
+        expect((yield* session.get(after.id)).projectID).toBe(migrated.project.id)
+      }),
+    { git: true },
+  )
+})