Function processMCPResult

src/services/mcp/client.ts:2720–2799

(
  result: unknown,
  tool: string, // Tool name for validation (e.g., "search")
  name: string, // Server name for IDE check and transformation (e.g., "slack")
)

}

export async function processMCPResult(
  result: unknown,
  tool: string, // Tool name for validation (e.g., "search")
  name: string, // Server name for IDE check and transformation (e.g., "slack")
): Promise<MCPToolResult> {
  const { content, type, schema } = await transformMCPResult(result, tool, name)

  // IDE tools are not going to the model directly, so we don't need to
  // handle large output.
  if (name === 'ide') {
    return content
  }

  // Check if content needs truncation (i.e., is too large)
  if (!(await mcpContentNeedsTruncation(content))) {
    return content
  }

  const sizeEstimateTokens = getContentSizeEstimate(content)

  // If large output files feature is disabled, fall back to old truncation behavior
  if (isEnvDefinedFalsy(process.env.ENABLE_MCP_LARGE_OUTPUT_FILES)) {
    logEvent('tengu_mcp_large_result_handled', {
      outcome: 'truncated',
      reason: 'env_disabled',
      sizeEstimateTokens,
    } as AnalyticsMetadata_I_VERIFIED_THIS_IS_NOT_CODE_OR_FILEPATHS)
    return await truncateMcpContentIfNeeded(content)
  }

  // Save large output to file and return instructions for reading it
  // Content is guaranteed to exist at this point (we checked mcpContentNeedsTruncation)
  if (!content) {
    return content
  }

  // If content contains images, fall back to truncation - persisting images as JSON
  // defeats the image compression logic and makes them non-viewable
  if (contentContainsImages(content)) {
    logEvent('tengu_mcp_large_result_handled', {
      outcome: 'truncated',
      reason: 'contains_images',
      sizeEstimateTokens,
    } as AnalyticsMetadata_I_VERIFIED_THIS_IS_NOT_CODE_OR_FILEPATHS)
    return await truncateMcpContentIfNeeded(content)
  }

  // Generate a unique ID for the persisted file (server__tool-timestamp)
  const timestamp = Date.now()
  const persistId = `mcp-${normalizeNameForMCP(name)}-${normalizeNameForMCP(tool)}-${timestamp}`
  // Convert to string for persistence (persistToolResult expects string or specific block types)
  const contentStr =
    typeof content === 'string' ? content : jsonStringify(content, null, 2)
  const persistResult = await persistToolResult(contentStr, persistId)

  if (isPersistError(persistResult)) {
    // If file save failed, fall back to returning truncated content info
    const contentLength = contentStr.length