[BUG] False positive content filter block when writing standard BSL 1.1 LICENSE file

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When asking Claude Code to write a Business Source License 1.1 (BUSL-1.1) LICENSE file for a software project, every attempt is blocked with:

API Error: 400 Output blocked by content filtering policy
or

This request triggered safety guardrails.
What I was trying to do:

Write a standard LICENSE file using the BSL 1.1 template (https://mariadb.com/bsl11/) with these fields filled in:

Licensor: ---
Additional Use Grant: free for personal/community/non-production use
Change Date: 2030-06-12
Change License: Apache-2.0
Why this is a false positive:

BSL 1.1 is a well-known public software license used by MariaDB, HashiCorp (Vault, Terraform before MPL re-license), Couchbase, and others. Writing a LICENSE file is a routine software engineering task. There is no harmful content involved.

Actual behavior: Blocked on every attempt across multiple sessions and model switches (Sonnet 4.6, Fable 5).

Workaround: None found. The block is consistent regardless of how the prompt is phrased.

Environment: Claude Code CLI, macOS, model claude-sonnet-4-6/Fable, and opus

What Should Happen?

Claude writes the LICENSE file.

Error Messages/Logs

API Error: 400 Output blocked by content filtering policy
or

This request triggered safety guardrails.
What I was trying to do:

Steps to Reproduce

When asking Claude Code to write a Business Source License 1.1 (BUSL-1.1) LICENSE file for a software project, every attempt is blocked with:

API Error: 400 Output blocked by content filtering policy
or

This request triggered safety guardrails.
What I was trying to do:

Write a standard LICENSE file using the BSL 1.1 template (https://mariadb.com/bsl11/) with these fields filled in:

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.1.175 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_