Function buildSendCascadeMessageRequest

src/windsurf.js:331–388

(apiKey, cascadeId, text, modelEnum, modelUid, sessionId, { toolPreamble, images, additionalSteps, nativeMode, nativeAllowlist, nativeEnvironment } = {})

 *          sees the next user turn. See src/cascade-native-bridge.js.
 */
export function buildSendCascadeMessageRequest(apiKey, cascadeId, text, modelEnum, modelUid, sessionId, { toolPreamble, images, additionalSteps, nativeMode, nativeAllowlist, nativeEnvironment } = {}) {
  const parts = [];

  // Field 1: cascade_id
  parts.push(writeStringField(1, cascadeId));

  // Field 2: TextOrScopeItem { text = 1 }
  parts.push(writeMessageField(2, writeStringField(1, text)));

  // Field 3: metadata
  parts.push(writeMessageField(3, buildMetadata(apiKey, undefined, sessionId)));

  // Field 5: cascade_config
  // DEFAULT mode enables vision but also activates Cascade's built-in tools
  // which conflict with our emulated tools. We force DEFAULT in two cases:
  //   - vision: images are attached AND no client tools are present.
  //   - native bridge: the caller's tools[] all map onto cascade-native
  //     IDE tools and v2.0.65 wants the planner's IDE agent loop alive
  //     (see src/cascade-native-bridge.js for rationale).
  const forceDefault = !!nativeMode || (!!images?.length && !toolPreamble);
  // v2.0.66 partition mode: when nativeMode is on AND a non-empty
  // toolPreamble was provided, the caller has unmapped tools that need
  // emulation alongside the mapped-tool native bridge. Pass toolPreamble
  // through so additional_instructions_section still carries those tool
  // definitions even though planner_mode is DEFAULT.
  const cascadeConfig = buildCascadeConfig(modelEnum, modelUid, {
    toolPreamble: toolPreamble || '',
    forceDefault,
    nativeMode: !!nativeMode,
    nativeAllowlist: nativeAllowlist || null,
    nativeEnvironment: nativeEnvironment || '',
  });
  parts.push(writeMessageField(5, cascadeConfig));

  // Field 6: images — repeated ImageData { base64_data=1, mime_type=2 }
  if (images?.length) {
    for (const img of images) {
      const imgMsg = Buffer.concat([
        writeStringField(1, img.base64_data),
        writeStringField(2, img.mime_type || 'image/png'),
      ]);
      parts.push(writeMessageField(6, imgMsg));
    }
  }

  // Field 9: additional_steps — repeated CortexTrajectoryStep. The native
  // bridge fills this with "we already executed view_file/run_command/...
  // and here are the results" steps so the planner reasons from the
  // post-tool state directly.
  if (Array.isArray(additionalSteps) && additionalSteps.length) {
    for (const stepBuf of additionalSteps) {
      if (!stepBuf || !Buffer.isBuffer(stepBuf) || stepBuf.length === 0) continue;
      parts.push(writeMessageField(9, stepBuf));
    }
  }

  return Buffer.concat(parts);
}