[DOCS] `--fallback-model` docs still say it is ignored in interactive sessions

Documentation Type

Incorrect/outdated documentation

Documentation Location

https://code.claude.com/docs/en/cli-reference

Section/Topic

--fallback-model in the CLI flags reference

Current Documentation

The CLI reference currently says:

--fallback-model | Enable automatic fallback to a specified model when the default model is overloaded. Takes effect in print mode (-p) and in background sessions, which run non-interactively; ignored in an interactive session

The changelog for v2.1.152 now says:

Claude Code now switches to your configured --fallback-model for the rest of the session when the primary model is not found, instead of failing every request

What's Wrong or Missing?

The --fallback-model reference is now outdated.

A. It still says interactive sessions ignore --fallback-model

The current CLI reference says the flag is ignored in an interactive session, but the v2.1.152 changelog describes new interactive-session behavior: when the primary model is not found, Claude Code switches to the configured fallback model instead of continuing to fail.

B. The trigger conditions are incomplete

The current text describes overload only. It does not mention the newly documented primary model is not found case.

C. Session persistence is undocumented

The changelog says Claude Code switches to the fallback model for the rest of the session. The current docs do not explain that this is a session-persistent change rather than a one-request retry.

Suggested Improvement

Update the --fallback-model row in cli-reference so it reflects the current behavior.

Suggested direction:

--fallback-model enables automatic fallback to a specified model when Claude Code cannot continue on the primary model. In v2.1.152 and later, this includes cases where the primary model is not found; Claude Code switches to the fallback model for the rest of the current session instead of failing each request. Document separately which fallback cases apply in print, background, and interactive sessions.

If interactive and non-interactive modes still differ for some fallback triggers, document those differences explicitly instead of saying interactive sessions ignore the flag.

Impact

Medium - Makes feature difficult to understand

Additional Context

Affected Pages:

| Page | Line(s) | Context |
|------|---------|---------|
| https://code.claude.com/docs/en/cli-reference | 72 | Still says --fallback-model is ignored in interactive sessions and only describes overload fallback |
| https://code.claude.com/docs/en/changelog | 22 | v2.1.152 says Claude Code now switches to the configured fallback model for the rest of the session when the primary model is not found |
| https://code.claude.com/docs/en/errors | 633-638 | Mentions some fallback scenarios, but does not describe the new model not found session-persistent fallback path |

Total scope: 3 pages affected

Source: Changelog v2.1.152

Exact changelog entry: Claude Code now switches to your configured --fallback-model for the rest of the session when the primary model is not found, instead of failing every request