Method setSessionConfigOption

packages/acp-adapter/src/server.ts:667–709

* Handle ACP `session/set_config_option` — the spec's generic * config-picker dispatch (PLAN D11). Routes by `params.configId`: * * - `'model'` → AcpSession.setModel (same path as * unstable_setSessionModel). * - `'mode'` → AcpSession.setMode (same path a

(
    params: SetSessionConfigOptionRequest,
  )

   * through the same notification channel with identical shape.
   */
  async setSessionConfigOption(
    params: SetSessionConfigOptionRequest,
  ): Promise<SetSessionConfigOptionResponse> {
    const acpSession = this.sessions.get(params.sessionId);
    if (!acpSession) {
      throw RequestError.invalidParams(
        { sessionId: params.sessionId },
        `Unknown sessionId: ${params.sessionId}`,
      );
    }
    const value = (params as { value: unknown }).value;
    switch (params.configId) {
      case 'model':
        await acpSession.setModel(String(value));
        break;
      case 'mode':
        await acpSession.setMode(String(value));
        break;
      case 'thinking': {
        // Phase 16 changed the wire shape from boolean to a 2-entry
        // `select` (`'on'` / `'off'`) for Zed UI compatibility. Strict
        // equality with `'on'` keeps the parse deterministic — any
        // other string (including a stale `true` / `false` boolean
        // sent by a pre-Phase-16 client) reads as "off" rather than
        // silently flipping based on truthiness.
        await acpSession.setThinking(value === 'on');
        break;
      }
      default:
        throw RequestError.invalidParams(
          { configId: params.configId },
          `Unknown configId: ${params.configId}`,
        );
    }
    return {
      configOptions: await buildSessionConfigOptions(
        this.harness,
        acpSession.currentModelId,
        acpSession.currentThinkingEnabled,
        acpSession.currentModeId,
      ),
    };
  }

  /**
   * Handle ACP `session/list`. Forwards to