Error reference changederrors
Nearest release: v2.1.318, published under an hour before upstream edited the page. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.
Upstream edited this page at 3 Nov 2026 22:38 UTC, give or take a minute or two: the time comes from Anthropic’s own sitemap rather than from a commit. This site recorded the change at 3 Nov 2026 23:07 UTC.
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Recorded edits218to this page, all time
#### `a hook changed this call's input after auto mode reviewed it`
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752752Auto mode is unavailable — the server returned no safety verdict for the last 10 responses, so Claude stopped. Send a message to try again, or switch out of auto mode.
753753```
754754
755Some denials don't count toward the ten, including [a denial from a hook or mod's change](#hook-changed-input-after-review).
756
755757The stop message appears in a different place in each kind of session:
756758
757759* In an interactive session, the message appears as a warning in the transcript and the turn ends
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771773
772774Before v2.1.302, on a direct connection to the Anthropic API, Claude Code didn't compact a conversation that had grown too long for the server's check.
773775
776#### `a hook changed this call's input after auto mode reviewed it`
777
778This denial means a hook or mod [changed the call's input](https://code.claude.com/docs/en/hooks.md#pretooluse-updatedinput-in-auto-mode) after the server reviewed it, so the review doesn't cover what would run. It isn't a judgment that the action is unsafe.
779
780Later calls in the same Claude response can be denied with this reason:
781
782```text theme={null}
783another call in this response was changed by a hook after auto mode reviewed it, or could not be confirmed unchanged
784```
785
786Claude can then issue each denied call again so the server reviews it. If a permission prompt opens, answer it. You don't need to do anything else unless Claude says in its reply that auto mode couldn't check the call. Then stop the change or approve the call yourself, and ask Claude to try the call again:
787
788* **Stop the change**: turn off the [hook](https://code.claude.com/docs/en/hooks.md#disable-or-remove-hooks) or [mod](https://code.claude.com/docs/en/plugins/mods/overview.md#turn-mods-on-or-off) that changed the call or an earlier call in the same Claude response, or ask your administrator to turn it off. To look for a hook, run [`/hooks`](https://code.claude.com/docs/en/hooks#the-%2Fhooks-menu) at the Claude Code prompt. In a terminal session, run `/plugin` to see the active mods.
789* **Approve the call yourself**: [switch to Manual mode](https://code.claude.com/docs/en/permission-modes.md#switch-permission-modes)
790
774791### Was not reviewed and did not run
775792
776793A `was not reviewed and did not run` denial means the conversation is too long for the [auto mode](https://code.claude.com/docs/en/permission-modes.md#eliminate-prompts-with-auto-mode) classifier to check the action, so the action didn't run. Claude Code returns this message to Claude:
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24972514A tool in the request declared an `input_schema` that fails the API's JSON Schema validation, so the API rejected the whole request. The number after `tools.` is the failing tool's position in the request's tool list, not a name you can look up.
24982515
24992516```text theme={null}
2500API Error: 400 ... tools.N.custom.input_schema: JSON schema is invalid
2501API Error: 400 ... tools.N.custom.input_schema.properties: Property keys should match pattern '^[a-zA-Z0-9_.-]{1,64}$'
2502```
2503
2504The first form means the schema isn't valid JSON Schema draft 2020-12. The second means a top-level property name doesn't match the pattern the message quotes.
2505
2506Claude Code [excludes MCP tools whose input schema would fail this validation](https://code.claude.com/docs/en/mcp.md#tools-with-invalid-input-schemas) when it loads a server's tools, so requests normally never include one.
2507
2508On a [deployment where flag fetching is off](https://code.claude.com/docs/en/env-vars.md#features-that-need-feature-flag-fetching), or on a machine whose flags have never arrived, Claude Code records in the server's log which tool would be rejected but sends it anyway, so this error can still occur.
2509
2510The error can also occur for a tool whose schema declares a JSON Schema dialect other than draft 2020-12 in `$schema`. Claude Code doesn't check those schemas against the JSON Schema meta-schema, though the top-level property-name check still applies.
2511
2512Before v2.1.216, no deployment ran the exclusion checks.
2513
2514**What to do:**
2515
2516* If your Claude Code version is earlier than v2.1.300, run [`claude update`](https://code.claude.com/docs/en/setup#update-claude-code) in your shell. Before v2.1.300, Claude Code didn't [retry the request without the rejected tool's parameters](https://code.claude.com/docs/en/mcp.md#tools-whose-input-schema-the-api-refuses), so this error repeated on every request that included the tool.
2517* Remove or [dis
2517API Error: 400 .
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