# Fix your first finding

Find and repair an empty tool description. Requires Python 3.10+ and [uv](https://docs.astral.sh/uv/getting-started/installation/). No clone or persistent package installation is required. Run these shell commands in a scratch directory.

## Create and scan

```sh
cat > agent.yaml <<'YAML'
system_prompt: |
  You are a support agent. Use the tools to help the user.
tools:
  - name: process_ticket
    description: ""
    parameters:
      type: object
      properties:
        ticket_id:
          type: string
YAML
uvx --from lintlang==0.8.0 lintlang scan agent.yaml --fail-on fail
```

Expected with the pinned release: **FAIL — 1 CRITICAL, 1 HIGH, 1 MEDIUM**, exit **1**. H1.1 identifies the empty description; H2 flags missing limits; H3 flags an undescribed parameter. A finding is a successful detection, not a broken installation.

## Repair and rerun

```sh
cat > agent-fixed.yaml <<'YAML'
system_prompt: |
  You are a support agent. Use the tools to help the user.
  Stop and report the failure once the retry limit is reached.
tools:
  - name: process_ticket
    description: "Apply a resolution action to one existing support ticket. Use this only after the ticket has been read; do NOT use it to look tickets up."
    parameters:
      type: object
      properties:
        ticket_id:
          type: string
          description: "Identifier of the existing ticket to act on"
      required: [ticket_id]
constraints:
  max_iterations: 3
  timeout_seconds: 30
YAML
uvx --from lintlang==0.8.0 lintlang scan agent-fixed.yaml --fail-on fail
```

Expected: **PASS — 0 findings**, exit **0**. This means the selected static checks found no covered defect; it is not a runtime-safety certificate.

## Gate your real instructions

```sh
uvx --from lintlang==0.8.0 lintlang scan AGENTS.md --fail-on fail
```

Replace AGENTS.md with an existing input you own. Without a threshold, scans are advisory. `--fail-on fail` gates HIGH/CRITICAL; `--fail-on review` also gates MEDIUM. Input errors remain nonzero. [Installation alternatives](/docs/install) include pip and pipx; [PowerShell examples](/docs/reference#windows-powershell) are in the reference.

Next: [Supported inputs](/docs/inputs) · [GitHub CI](/integrations/github) · [GitLab CI](/integrations/gitlab) · [Rules](/rules) · [Integrations](/integrations).