终端 Agent Runtime
从重建源码看 Claude Code 到底重在哪

// src/main.tsx
// These side-effects must run before all other imports:
profileCheckpoint('main_tsx_entry')
startMdmRawRead()
startKeychainPrefetch()

// src/entrypoints/init.ts
// Apply only safe environment variables before trust dialog
// Full environment variables are applied after trust is established
applySafeConfigEnvironmentVariables()

/**
 * One QueryEngine per conversation.
 * State (messages, file cache, usage, etc.) persists across turns.
 */
export class QueryEngine {
  private mutableMessages: Message[]
  private permissionDenials: SDKPermissionDenial[]
  private totalUsage: NonNullableUsage
  private loadedNestedMemoryPaths = new Set<string>()
}

// Skill discovery prefetch — per-iteration ...
// Discovery runs while the model streams and tools execute
const pendingSkillPrefetch = skillPrefetch?.startSkillDiscoveryPrefetch(
  null,
  messages,
  toolUseContext,
)

yield { type: 'stream_request_start' }

isConcurrencySafe(input): boolean
isReadOnly(input): boolean
interruptBehavior?(): 'cancel' | 'block'
renderToolUseMessage(...)

// Defaults (fail-closed where it matters):
// - isConcurrencySafe → false
// - isReadOnly → false

if (serverRef.type === 'sse') {
  const authProvider = new ClaudeAuthProvider(name, serverRef)
  const transportOptions = { authProvider, fetch: wrapFetchWithTimeout(...) }
  transport = new SSEClientTransport(new URL(serverRef.url), transportOptions)
} else if (serverRef.type === 'http') {
  const authProvider = new ClaudeAuthProvider(name, serverRef)
  const transportOptions = { authProvider, fetch: wrapFetchWithTimeout(...) }
  transport = new StreamableHTTPClientTransport(new URL(serverRef.url), transportOptions)
}

// src/memdir/memdir.ts
`${ENTRYPOINT_NAME}` is an index, not a memory
lines after ${MAX_ENTRYPOINT_LINES} will be truncated

// src/interactiveHelpers.tsx
// The trust dialog is the workspace trust boundary
// ... bypassPermissions mode only affects tool execution permissions