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.
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API Error 400 (invalid_request_error)
The request itself was malformed or violated a schema constraint.
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API Error 500 (internal server error)
A server-side failure on the API, usually transient but sometimes build-specific.
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API Error 401 (authentication_error)
The API rejected the credential attached to the request.
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API Error 429 (rate_limit_error)
The API rejected the request for exceeding a rate or usage limit.
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API Error 529 (overloaded_error)
Anthropic capacity saturation: the model is temporarily overloaded.
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API Error 403 (permission_error)
The credential is valid but not allowed to use this model, org, or endpoint.
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API Error 413 (request_too_large)
The payload exceeded the maximum request size the API accepts.
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Model not found (not_found_error)
A requested model id is unavailable to this account or was retired.
Filesystem & permission errors
POSIX errno codes raised while reading, writing, or executing.
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ENOENT: no such file or directory
A path Claude Code tried to open does not exist at that location.
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EISDIR: illegal operation on a directory
A directory path was handed to a call that expects a file.
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EACCES / EPERM: permission denied
The OS refused a read, write, or exec because of file ownership or mode.
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ENOTEMPTY: directory not empty
A remove or rename targeted a directory that still has contents.
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EEXIST: file already exists
A create or mkdir hit a path that is already taken.
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EBUSY: resource busy or locked
Another process holds the file or device Claude Code needs.
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EXDEV: cross-device link not permitted
A rename crossed a filesystem boundary, which the OS will not do atomically.
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ENOSPC: no space left on device
The disk or inode table filled up mid-operation.
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EPIPE: broken pipe
Claude Code wrote to a pipe whose reader had already gone away.
Network & TLS errors
Socket, DNS, proxy, and certificate failures reaching the API.
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ECONNRESET: socket hang up
The peer tore the TCP connection down mid-request.
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ECONNREFUSED: connection refused
Nothing was listening at the address Claude Code dialled.
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Self-signed certificate in certificate chain
A TLS-inspecting proxy presented a certificate Node will not trust.
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ETIMEDOUT: request timed out
A socket exceeded its timeout before the response arrived.
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getaddrinfo ENOTFOUND (DNS lookup failed)
The hostname failed to resolve, usually DNS or a proxy rewrite.
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EADDRINUSE: address already in use
A port Claude Code wanted to bind is already held by another process.
Node runtime crashes
JavaScript exceptions, heap exhaustion, and fatal signals.
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AbortError: the operation was aborted
An in-flight request was cancelled by an abort signal or timeout.
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SyntaxError: Unexpected token
A parse failed, most often on config or a truncated JSON response.
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Killed: 9 (SIGKILL / OOM killer)
The kernel terminated Claude Code outright, usually for memory pressure.
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Segmentation fault (SIGSEGV / SIGABRT)
The process died at the native layer rather than throwing a JS error.
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TypeError: Cannot read properties of undefined
A property access on undefined or null crashed the CLI.
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JavaScript heap out of memory
V8 exhausted its heap and aborted the process.
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Unhandled promise rejection
An async failure escaped every catch and reached the process handler.
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RangeError: Maximum call stack size exceeded
Unbounded recursion blew the JS stack.
Session, auth & limit messages
Login, quota, and context-window messages surfaced in the CLI.
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Claude usage limit reached
The plan quota was consumed and the session paused until reset.
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Auto-compact / compaction failed
The conversation-compaction step errored or looped instead of shrinking context.
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OAuth token expired / refresh failed
The stored OAuth token lapsed and the refresh did not recover it.
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Prompt is too long (context window exceeded)
The assembled prompt exceeded the model context window.
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Invalid API key (invalid x-api-key)
The key in the environment or keychain was rejected outright.
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Your credit balance is too low
The workspace ran out of prepaid credit for API calls.
Tooling & integration errors
MCP, shell spawn, npm, and terminal-rendering failures.
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Garbled / flickering terminal output
Escape-sequence handling corrupts the rendered TUI in some terminals.
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spawn ENOENT / command not found
A shell or tool binary was not on PATH when Claude Code tried to run it.
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MCP server failed to start or connect
A configured MCP server never completed its handshake or dropped out.
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.