docs(mcp): align tool docs with codex parity

- Document web_search as the canonical MCP tool name and retain the legacy web.search alias across README, changelog, and mode docs.
- Explain how to mirror Codex CLI MCP installs with codex mcp add and note the common server bundle.
- Point the configuration guide at spec-compliant naming and runtime toggles for Codex users.

Acceptance Criteria:
- Documentation stops advertising dotted tool names as canonical and references Codex-compatible installs.

Test Notes:
- docs-only change; no automated tests run.

docs/configuration.md

@@ -202,9 +202,9 @@ Requests target the same `/api/chat` endpoint documented by Ollama and automatic
 
 The quota fields are optional and purely informational—they are never sent to the provider. Owlen uses them to display hourly/weekly token usage in the chat header, emit pre-limit toasts at 80% and 95%, and power the `:limits` command. Adjust the numbers to reflect the soft limits on your account or remove the keys altogether if you do not want usage tracking.
 
-If your deployment exposes the web search endpoint under a different path, set `web_search_endpoint` in the same table. The default (`/api/web_search`) matches the Ollama Cloud REST API documented in the web retrieval guide.
+If your deployment exposes the web search endpoint under a different path, set `web_search_endpoint` in the same table. The default (`/api/web_search`) matches the Ollama Cloud REST API documented in the web retrieval guide. Tools should be registered as `web_search` to stay within MCP’s identifier rules; Owlen keeps `web.search` as a backward-compatible alias but treats the underscored form as canonical.citeturn6view0
 
-Toggle the feature at runtime with `:web on` / `:web off` from the TUI or `owlen providers web --enable/--disable` on the CLI; both commands persist the change back to `config.toml`.
+Toggle the feature at runtime with `:web on` / `:web off` from the TUI or `owlen providers web --enable/--disable` on the CLI; both commands persist the change back to `config.toml`. Codex users can mirror this setup by running `codex mcp add` for each server (Context7, Figma, Playwright, Chrome DevTools, Sentry, GitHub, etc.) and then binding the exposed tool identifiers to Owlen’s registry.citeturn4view0turn6view0
 
 > **Tip:** If the official `ollama signin` flow fails on Linux v0.12.3, follow the [Linux Ollama sign-in workaround](#linux-ollama-sign-in-workaround-v0123) in the troubleshooting guide to copy keys from a working machine or register them manually.
 

docs/phase5-mode-system.md

@@ -14,7 +14,7 @@ Phase 5 has been fully implemented according to the specification in `.agents/ne
 - `ModeConfig` for configuring tool availability per mode
 - `ModeToolConfig` with wildcard (`*`) support for allowing all tools
 - Default configuration:
-  - Chat mode: only `web_search` allowed
+  - Chat mode: only `web_search` allowed (legacy `web.search` alias still resolves)
   - Code mode: all tools allowed (`*`)
 
 ### 2. Configuration Integration (✅ Complete)
@@ -27,7 +27,7 @@ Phase 5 has been fully implemented according to the specification in `.agents/ne
 
 ```toml
 [modes.chat]
-allowed_tools = ["web_search"]
+allowed_tools = ["web_search"]  # Legacy `web.search` alias still accepted
 
 [modes.code]
 allowed_tools = ["*"]  # All tools allowed
@@ -132,6 +132,7 @@ default_model = "llama3.2:latest"
 
 [modes.chat]
 # In chat mode, only web search is allowed
+# When migrating older configs you can still list `web.search`, but Owlen rewrites it internally.
 allowed_tools = ["web_search"]
 
 [modes.code]
@@ -166,7 +167,7 @@ owlen -c
 ### Tool Filtering Behavior
 
 **In Chat Mode:**
-- ✅ `web_search` - Allowed
+- ✅ `web_search` - Allowed (legacy `web.search` alias also resolves)
 - ❌ `code_exec` - Blocked (suggests switching to code mode)
 - ❌ `file_write` - Blocked
 - ❌ `file_delete` - Blocked