refactor(core): replace deferred tool option with codemode

packages/codemode/AGENTS.md

@@ -4,7 +4,7 @@
 - Do not add a speculative generic permission or approval policy. A host omits tools it does not expose and enforces domain authorization inside each provided tool.
 - Keep Code Mode unaware of host session, channel, and conversation models. The hosting application supplies trusted execution scope around it.
 - Tool schemas are the model-facing Interface. Keep arguments minimal and natural to the operation; never add unrelated IDs as ambient capability tokens.
-- When interpreter behavior or support changes, update `interpreter-support.md` and direct tests in the same PR. Update `codemode.md` when the package design, integration status, or rationale changes.
+- When interpreter behavior or support changes, update `interpreter-support.md` and direct tests in the same PR.
 
 ## OpenAPI
 

packages/core/src/flag/flag.ts

@@ -52,9 +52,6 @@ export const Flag = {
   get OPENCODE_EXPERIMENTAL_REFERENCES() {
     return enabledByExperimental("OPENCODE_EXPERIMENTAL_REFERENCES")
   },
-  get CODEMODE_ENABLED() {
-    return process.env["CODEMODE_ENABLED"] === undefined || truthy("CODEMODE_ENABLED")
-  },
   get OPENCODE_TUI_CONFIG() {
     return process.env["OPENCODE_TUI_CONFIG"]
   },

packages/core/src/mcp/guidance.ts

@@ -1,7 +1,6 @@
 export * as McpGuidance from "./guidance"
 
 import { makeLocationNode } from "../effect/app-node"
-import { Flag } from "../flag/flag"
 import { Context, Effect, Layer, Schema } from "effect"
 import { AgentV2 } from "../agent"
 import { PermissionV2 } from "../permission"
@@ -18,11 +17,7 @@ type Summary = typeof Summary.Type
 const entries = (servers: ReadonlyArray<Summary>) =>
   servers.flatMap((server) => [
     `  <server name="${server.server}">`,
-    ...(Flag.CODEMODE_ENABLED
-      ? [
-          `    Use tools from this server through \`execute\` under \`tools[${JSON.stringify(McpTool.group(server.server))}]\`.`,
-        ]
-      : []),
+    `    Use tools from this server through \`execute\` under \`tools[${JSON.stringify(McpTool.group(server.server))}]\`.`,
     ...server.instructions.split("\n").map((line) => `    ${line}`),
     "  </server>",
   ])
@@ -81,7 +76,7 @@ export const layer = Layer.effect(
               removed: () => "MCP server instructions are no longer available.",
             },
           })
-        if (Flag.CODEMODE_ENABLED && PermissionV2.evaluate("execute", "*", agent.permissions).effect === "deny")
+        if (PermissionV2.evaluate("execute", "*", agent.permissions).effect === "deny")
           return source(Instructions.removed)
         const [instructions, tools] = yield* Effect.all([mcp.instructions(), mcp.tools()], {
           concurrency: "unbounded",
@@ -90,12 +85,9 @@ export const layer = Layer.effect(
         const visible = instructions
           .filter((item) => {
             const owned = tools.filter((tool) => tool.server === item.server)
-            return (
-              (!Flag.CODEMODE_ENABLED && owned.length === 0) ||
-              owned.some(
-                (tool) =>
-                  PermissionV2.evaluate(McpTool.name(tool.server, tool.name), "*", agent.permissions).effect !== "deny",
-              )
+            return owned.some(
+              (tool) =>
+                PermissionV2.evaluate(McpTool.name(tool.server, tool.name), "*", agent.permissions).effect !== "deny",
             )
           })
           .map((item) => ({ server: item.server, instructions: item.instructions }))

packages/core/src/tool/AGENTS.md

@@ -29,7 +29,8 @@ Leaves own resolution, permission, and side-effect ordering. Translate only expe
 ## Registration
 
 Built-ins and plugin tools register through `Tools.Service.register({ [name]: tool })`. Registrations may provide a
-group, which flattens direct model names to `<group>_<tool>`, and may be deferred from direct model exposure.
+group, which flattens direct model names to `<group>_<tool>`, and default into CodeMode (`codemode` defaults true;
+`codemode: false` keeps the tool on the provider's native tool list).
 
 Registrations are scoped:
 

packages/core/src/tool/edit.ts

@@ -212,6 +212,7 @@ export const Plugin = {
             }),
             "edit",
           ),
+          { codemode: false },
         ),
       )
       .pipe(Effect.orDie)

packages/core/src/tool/execute.ts

@@ -58,16 +58,16 @@ export const create = (registrations: ReadonlyMap<string, Registration>) => {
       })
       if (registration.group === undefined) {
         const path = registration.name
-        if (Object.hasOwn(tools, path)) throw new TypeError(`Deferred tool namespace conflict: ${path}`)
+        if (Object.hasOwn(tools, path)) throw new TypeError(`CodeMode tool namespace conflict: ${path}`)
         tools[path] = value
         continue
       }
       const path = registration.name
       const namespace = registration.group
       const group = tools[namespace]
-      if (group && Tool.isDefinition(group)) throw new TypeError(`Deferred tool namespace conflict: ${namespace}`)
+      if (group && Tool.isDefinition(group)) throw new TypeError(`CodeMode tool namespace conflict: ${namespace}`)
       if (group) {
-        if (Object.hasOwn(group, path)) throw new TypeError(`Deferred tool namespace conflict: ${namespace}.${path}`)
+        if (Object.hasOwn(group, path)) throw new TypeError(`CodeMode tool namespace conflict: ${namespace}.${path}`)
         group[path] = value
         continue
       }

packages/core/src/tool/glob.ts

@@ -106,6 +106,7 @@ export const Plugin = {
                 ),
               ),
           }),
+          { codemode: false },
         ),
       )
       .pipe(Effect.orDie)

packages/core/src/tool/grep.ts

@@ -137,6 +137,7 @@ export const Plugin = {
                 ),
               ),
           }),
+          { codemode: false },
         ),
       )
       .pipe(Effect.orDie)

packages/core/src/tool/mcp.ts

@@ -5,7 +5,7 @@ import { McpEvent } from "@opencode-ai/schema/mcp-event"
 import { Effect, Exit, type JsonSchema, Layer, Scope, Semaphore, Stream } from "effect"
 import { makeLocationNode } from "../effect/app-node"
 import { EventV2 } from "../event"
-import { Flag } from "../flag/flag"
+
 import { MCP } from "../mcp"
 import { PermissionV2 } from "../permission"
 import { Tool } from "./tool"
@@ -107,7 +107,7 @@ export const layer = Layer.effectDiscard(
         const next = yield* Scope.fork(scope)
         yield* Effect.forEach(
           groups,
-          ([group, record]) => tools.register(record, { group, deferred: Flag.CODEMODE_ENABLED }),
+          ([group, record]) => tools.register(record, { group }),
           {
             discard: true,
           },

packages/core/src/tool/patch.ts

@@ -191,6 +191,7 @@ export const Plugin = {
             }),
             "edit",
           ),
+          { codemode: false },
         ),
       )
       .pipe(Effect.orDie)

packages/core/src/tool/question.ts

@@ -106,6 +106,7 @@ export const Plugin = {
                   }),
                 ),
           }),
+          { codemode: false },
         ),
       )
       .pipe(Effect.orDie)

packages/core/src/tool/read.ts

@@ -139,6 +139,7 @@ export const Plugin = {
               )
             },
           }),
+          { codemode: false },
         ),
       )
       .pipe(Effect.orDie)