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Guardrail Fallback Linter

Find the LLM calls that break when a model blocks a response or falls back to another model.

Format: Agent skill, not a browser app. You need an AI agent that can load its instructions and use the required tools.

Package requirements: Agents that read the open SKILL.md format. Verify runtime and service requirements at the purchase or install destination.

You get: Read-only findings on call sites that may mishandle blocked responses or model fallback. Findings depend on the integration code supplied.

Licence and purchase details

Review the package licence at the destination.

Review the offer and access method at your chosen marketplace. Agensi provides connected-agent access, not a download. Buying a skill does not include an AI-agent subscription or setup service.

Agensi access: This product’s bundled-script workflow through Agensi has not been verified here. Tests of other products do not establish this package’s compatibility. Local setup examples apply to separately obtained downloadable packages.

See tested hosts, versions and workflow limits.

What it does

With Claude Fable 5, a call in a high-risk domain can be blocked and fall back to Claude Opus 4.8. Code that parses the response blind will break, or worse, quietly run on a downgraded answer nobody decided to accept. Guardrail Fallback Linter finds the call sites where that can happen.

It scans your source for LLM calls that assume every response is a usable answer: a call with no error or refusal branch, a response parsed with no guard, a hardcoded model id with no fallback handling. You get each finding so you can handle the block and the fallback on purpose instead of discovering it in production.

It reads files only. It does not run your code, call any model, or touch the network.

What it checks

What the output looks like

guardrail-fallback-linter
$ scan_guardrail_fallback.py src/
 
GFL001 HIGH client.py:42 response parsed, no refusal branch
GFL002 MED client.js:17 hardcoded model id, no fallback
 
read-only 2 findings, see remediation-snippets.md

One thing this is not

This is a reliability check. It helps you handle a guardrail block and a model fallback gracefully so your app degrades on purpose. It is not, and must not be used as, a way to bypass, weaken, or evade any safety guardrail.

// choose with context

Is Guardrail Fallback Linter the right skill?

Best fit

Review LLM integration code for response-blocking and fallback handling gaps.

It returns

Read-only findings on call sites that may mishandle blocked responses or model fallback. Findings depend on the integration code supplied.

Do not use it as

Do not treat a successful run as proof beyond the supplied files, declared scope, and evidence the skill actually checked.

Compatibility, access, version, and licence

Reads or accesses
Only the files or context you deliberately provide; review the listing before granting additional access.
Compatibility
Agents that read the open SKILL.md format. Verify runtime and service requirements at the purchase or install destination.
Version
Verify the current package version at the linked destination.
Licence
Review the package licence and seller terms at the linked destination.

What happens next

Open the Agensi listing, check the current offer and connect a supported agent. Agensi loads the skill through its connector; it no longer provides a download. Approve any purchase before use. Check Agensi’s current connection guide before changing an existing connection.

Questions

Does it run my code or call a model?

No. It reads your source files only. It does not run your code, call any model, or touch the network.

Which languages does it cover?

Python and JavaScript or TypeScript, using an editable list of common client call patterns. Detection is heuristic: it flags likely-unhandled call sites for review.

Is this a way around safety guardrails?

No. It is a reliability check that helps you handle a block and a fallback gracefully. It is not a way to bypass, weaken, or evade any safety guardrail.

Handle the block and the fallback on purpose.

Current price and purchase option are shown on Agensi. Use a supported agent connection on Agensi. Review the requirements above before getting started.

Get Guardrail Fallback Linter on Agensi