API_TIMEOUT_MS
A Claude Code environment variable, read out of the shipped bundle. It has been in the build since v2.1.138, including the newest one read.
What it is
Timeout for API requests in milliseconds (default: 600000, or 10 minutes; maximum: 2147483647). Increase this when requests time out on slow networks or when routing through a proxy. Values above the maximum overflow the underlying timer and cause requests to fail immediately
Anthropic's own wording. Read off Environment variables, captured 2026-08-28.
Presence across releases
| Releases | Reading | Declared type | Default |
|---|---|---|---|
| 2.1.245 – 2.1.250 5 releases | never mined | — | — |
| 2.1.242 – 2.1.243 2 releases | in the build | — | — |
| 2.1.160 – 2.1.241 73 releases | in the build | int | — |
| 2.1.138 – 2.1.159 20 releases | in the build | — | — |
A row reading never mined is a release with no archived bundle behind it. Nothing was read out of it, so nothing here says whether the name was in it. A declared type or a default is only ever what that release's own bundle stated.
Changelog entries naming it
-
v2.1.242API requests that never send response headers are now aborted
Hung requests are aborted when headers never arrive, and you can tune the window.
named in this entry
Documentation pages
- Environment variables reference table Claude Code CLI
- Agent SDK reference - Python mentions it Claude Code CLI
- Agent SDK reference - TypeScript mentions it Claude Code CLI
- Error reference mentions it Claude Code CLI
A reference table page is one whose own table defines this name, and it is where the description above came from. A page that mentions it carries the name somewhere in its text and may say nothing about it at all. Every page carrying it.
Names beside it
Every environment variable in the inventory starting api, up to twelve of them.
API_FORCE_IDLE_TIMEOUTOverride the 5-minute body idle timeout that aborts a streaming model response when no bytes arrive. Set to 0 to turn the timeout off, for example when a slow [gateway](/docs/en/llm-gateway) or local model pauses longer than 5 minutes between chunks, or 1 to keep it on for every provider. When unset, the timeout is active on providers other than the direct Anthropic API and [Claude Platform on AWS](/docs/en/claude-platform-on-aws). The [stream watchdogs](/docs/en/network-config#streaming-idle-watchdogs) run independently of it and abort a long silent pause even when you set 0 here. Requires Claude Code v2.1.169 or later 2.1.138
API_MAX_INPUT_TOKENSNo description from anybody. 2.1.160
API_TARGET_INPUT_TOKENSNo description from anybody. 2.1.160
API_TOKENNo description from anybody. 2.1.160
Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the environment variable does. All environment variables.