Function analyzeContextUsage

src/utils/analyzeContext.ts:940–1412

(
  messages: Message[],
  model: string,
  getToolPermissionContext: () => Promise<ToolPermissionContext>,
  tools: Tools,
  agentDefinitions: AgentDefinitionsResult,
  terminalWidth?: number,
  toolUseContext?: Pick<ToolUseContext, 'options'>,
  mainThreadAgentDefinition?: AgentDefinition,
  /** Original messages before microcompact, used to extract API usage */
  originalMessages?: Message[],
)

}

export async function analyzeContextUsage(
  messages: Message[],
  model: string,
  getToolPermissionContext: () => Promise<ToolPermissionContext>,
  tools: Tools,
  agentDefinitions: AgentDefinitionsResult,
  terminalWidth?: number,
  toolUseContext?: Pick<ToolUseContext, 'options'>,
  mainThreadAgentDefinition?: AgentDefinition,
  /** Original messages before microcompact, used to extract API usage */
  originalMessages?: Message[],
): Promise<ContextData> {
  const runtimeModel = getRuntimeMainLoopModel({
    permissionMode: (await getToolPermissionContext()).mode,
    mainLoopModel: model,
  })
  // Get context window size
  const contextWindow = getContextWindowForModel(runtimeModel, getSdkBetas())

  // Build the effective system prompt using the shared utility
  const defaultSystemPrompt = await getSystemPrompt(tools, runtimeModel)
  const effectiveSystemPrompt = buildEffectiveSystemPrompt({
    mainThreadAgentDefinition,
    toolUseContext: toolUseContext ?? {
      options: {} as ToolUseContext['options'],
    },
    customSystemPrompt: toolUseContext?.options.customSystemPrompt,
    defaultSystemPrompt,
    appendSystemPrompt: toolUseContext?.options.appendSystemPrompt,
  })

  // Critical operations that should not fail due to skills
  const [
    { systemPromptTokens, systemPromptSections },
    { claudeMdTokens, memoryFileDetails },
    {
      builtInToolTokens,
      deferredBuiltinDetails,
      deferredBuiltinTokens,
      systemToolDetails,
    },
    { mcpToolTokens, mcpToolDetails, deferredToolTokens },
    { agentTokens, agentDetails },
    { slashCommandTokens, commandInfo },
    messageBreakdown,
  ] = await Promise.all([
    countSystemTokens(effectiveSystemPrompt),
    countMemoryFileTokens(),
    countBuiltInToolTokens(
      tools,
      getToolPermissionContext,
      agentDefinitions,
      runtimeModel,
      messages,
    ),
    countMcpToolTokens(
      tools,
      getToolPermissionContext,