Claude Code Errors by Exact Message

When Claude Code fails it prints a specific string. These 40 pages index 14,999 issue reports by that string, so you can search the way you actually have it — pasted from your terminal. Each page adds the backlog trend, the builds that report it, resolution times, and workarounds pulled from the threads.

Only error strings backed by at least 25 real reports get a page. Signatures are hand-written, not auto-mined — see the note at the bottom.

Anthropic API errors

HTTP status and error-type responses returned by the API.

  1. API Error 400 (invalid_request_error)

    The request itself was malformed or violated a schema constraint.

    2,591 issues 129 open ✓ 447 workaround mentions
  2. API Error 500 (internal server error)

    A server-side failure on the API, usually transient but sometimes build-specific.

    603 issues 11 open ✓ 26 workaround mentions
  3. API Error 401 (authentication_error)

    The API rejected the credential attached to the request.

    441 issues 48 open ✓ 80 workaround mentions
  4. API Error 429 (rate_limit_error)

    The API rejected the request for exceeding a rate or usage limit.

    690 issues 23 open ✓ 21 workaround mentions
  5. API Error 529 (overloaded_error)

    Anthropic capacity saturation: the model is temporarily overloaded.

    254 issues 27 open ✓ 13 workaround mentions
  6. API Error 403 (permission_error)

    The credential is valid but not allowed to use this model, org, or endpoint.

    235 issues 42 open ✓ 47 workaround mentions
  7. API Error 413 (request_too_large)

    The payload exceeded the maximum request size the API accepts.

    38 issues 2 open ✓ 7 workaround mentions
  8. Model not found (not_found_error)

    A requested model id is unavailable to this account or was retired.

    83 issues 4 open ✓ 8 workaround mentions

Filesystem & permission errors

POSIX errno codes raised while reading, writing, or executing.

  1. ENOENT: no such file or directory

    A path Claude Code tried to open does not exist at that location.

    1,200 issues 64 open ✓ 210 workaround mentions
  2. EISDIR: illegal operation on a directory

    A directory path was handed to a call that expects a file.

    495 issues 9 open ✓ 18 workaround mentions
  3. EACCES / EPERM: permission denied

    The OS refused a read, write, or exec because of file ownership or mode.

    415 issues 71 open ✓ 128 workaround mentions
  4. ENOTEMPTY: directory not empty

    A remove or rename targeted a directory that still has contents.

    88 issues 9 open ✓ 19 workaround mentions
  5. EEXIST: file already exists

    A create or mkdir hit a path that is already taken.

    138 issues 12 open ✓ 65 workaround mentions
  6. EBUSY: resource busy or locked

    Another process holds the file or device Claude Code needs.

    127 issues 18 open ✓ 35 workaround mentions
  7. EXDEV: cross-device link not permitted

    A rename crossed a filesystem boundary, which the OS will not do atomically.

    91 issues 11 open ✓ 52 workaround mentions
  8. ENOSPC: no space left on device

    The disk or inode table filled up mid-operation.

    62 issues 4 open ✓ 22 workaround mentions
  9. EPIPE: broken pipe

    Claude Code wrote to a pipe whose reader had already gone away.

    57 issues 2 open ✓ 11 workaround mentions

Network & TLS errors

Socket, DNS, proxy, and certificate failures reaching the API.

  1. ECONNRESET: socket hang up

    The peer tore the TCP connection down mid-request.

    229 issues 70 open ✓ 50 workaround mentions
  2. ECONNREFUSED: connection refused

    Nothing was listening at the address Claude Code dialled.

    207 issues 9 open ✓ 15 workaround mentions
  3. Self-signed certificate in certificate chain

    A TLS-inspecting proxy presented a certificate Node will not trust.

    41 issues 6 open ✓ 20 workaround mentions
  4. ETIMEDOUT: request timed out

    A socket exceeded its timeout before the response arrived.

    28 issues 9 open ✓ 6 workaround mentions
  5. getaddrinfo ENOTFOUND (DNS lookup failed)

    The hostname failed to resolve, usually DNS or a proxy rewrite.

    49 issues 17 open ✓ 19 workaround mentions
  6. EADDRINUSE: address already in use

    A port Claude Code wanted to bind is already held by another process.

    30 issues 5 open ✓ 13 workaround mentions

Node runtime crashes

JavaScript exceptions, heap exhaustion, and fatal signals.

  1. AbortError: the operation was aborted

    An in-flight request was cancelled by an abort signal or timeout.

    2,101 issues 47 open ✓ 98 workaround mentions
  2. SyntaxError: Unexpected token

    A parse failed, most often on config or a truncated JSON response.

    698 issues 30 open ✓ 69 workaround mentions
  3. Killed: 9 (SIGKILL / OOM killer)

    The kernel terminated Claude Code outright, usually for memory pressure.

    337 issues 107 open ✓ 165 workaround mentions
  4. Segmentation fault (SIGSEGV / SIGABRT)

    The process died at the native layer rather than throwing a JS error.

    289 issues 79 open ✓ 97 workaround mentions
  5. TypeError: Cannot read properties of undefined

    A property access on undefined or null crashed the CLI.

    194 issues 9 open ✓ 49 workaround mentions
  6. JavaScript heap out of memory

    V8 exhausted its heap and aborted the process.

    142 issues 4 open ✓ 31 workaround mentions
  7. Unhandled promise rejection

    An async failure escaped every catch and reached the process handler.

    59 issues 1 open ✓ 15 workaround mentions
  8. RangeError: Maximum call stack size exceeded

    Unbounded recursion blew the JS stack.

    30 issues 1 open ✓ 8 workaround mentions

Session, auth & limit messages

Login, quota, and context-window messages surfaced in the CLI.

  1. Claude usage limit reached

    The plan quota was consumed and the session paused until reset.

    173 issues 27 open ✓ 27 workaround mentions
  2. Auto-compact / compaction failed

    The conversation-compaction step errored or looped instead of shrinking context.

    379 issues 31 open ✓ 98 workaround mentions
  3. OAuth token expired / refresh failed

    The stored OAuth token lapsed and the refresh did not recover it.

    344 issues 91 open ✓ 116 workaround mentions
  4. Prompt is too long (context window exceeded)

    The assembled prompt exceeded the model context window.

    322 issues 20 open ✓ 47 workaround mentions
  5. Invalid API key (invalid x-api-key)

    The key in the environment or keychain was rejected outright.

    99 issues 6 open ✓ 18 workaround mentions
  6. Your credit balance is too low

    The workspace ran out of prepaid credit for API calls.

    76 issues 11 open ✓ 6 workaround mentions

Tooling & integration errors

MCP, shell spawn, npm, and terminal-rendering failures.

  1. Garbled / flickering terminal output

    Escape-sequence handling corrupts the rendered TUI in some terminals.

    829 issues 148 open ✓ 247 workaround mentions
  2. spawn ENOENT / command not found

    A shell or tool binary was not on PATH when Claude Code tried to run it.

    506 issues 58 open ✓ 217 workaround mentions
  3. MCP server failed to start or connect

    A configured MCP server never completed its handshake or dropped out.

    229 issues 45 open ✓ 78 workaround mentions

How these pages are built

Every signature below is hand-written. We tried mining uppercase tokens automatically and the real corpus returned ENTIRE, EDITOR, EVERY and EXACTLY as if they were errno codes — which would have shipped dozens of nonsense pages. Curation is the whole point: a page exists only when a string a human would actually paste into a search box has at least 25 real reports behind it.