BD CORS Audit
CORS (Cross-Origin Resource Sharing) misconfiguration auditor. Probes any API endpoint with crafted Origin headers to detect the most dangerous CORS vulnerabilities — reflecting arbitrary Origins (any attacker.com gets CORS approved), Access-Control-Allow-Credentials:true with wildcard ACAO, null-Origin allowed (iframe/file:// bypass), subdomain regex bypasses (evil.myapp.com passes), missing Vary:Origin (CDN cache poisoning), and permissive preflight responses. Also scans source code for insecure CORS middleware patterns (Express/FastAPI/Go/Rails/Django/Spring). Generates correct CORS configuration for your specific stack. Works against any live URL via curl — zero external API. Triggers on "CORS error", "CORS misconfiguration", "Access-Control-Allow-Origin", "cors policy", "preflight", "cors blocked", "/cors-audit".
As a process D 43/100 · Unfinished process — weak spots: result and completion, inputs and preconditions, failures and branches
How to improve
- Say in the description WHEN to use the skill ("use when…", example requests): that is the agent's main cue.
- The SKILL.md body is over 5,000 tokens: move reference detail into references/ and load it when needed.
- Your own cases (evals/evals.json, 4–6 real requests with expected answers): the full check would then run those instead of a model-drafted suite.
- A spec.yaml with trigger phrases and assertions — a behaviour contract for CI; `skilltest init` writes a template.
Guard findings · 0
✓ No critical or high findings
Files scanned: 2. Evidence is masked. Grey chips explain why severity was lowered.
Against the Agent Skills spec
- warning
name-formatname should be kebab-case (lowercase letters, digits, hyphens) - warning
description-no-whendescription does not say WHEN to use the skill (no "use when") - warning
body-longSKILL.md body ≈ 6382 tokens (recommended < 5000); move details to references/ - note
frontmatter-keyunknown frontmatter key "homepage"
Process rating: all ten parameters 43/100
- 0Result and completion. Does not say what the result is
- 0Inputs and preconditions. Does not say what the process needs to start
- 0Failures and branches. Linear process with no failure handling
- 0Progress reporting. Says nothing while it works
- 30Running it twice. 1 mutating operations with no state check
- 40Consistency. Frontmatter name (CORS Audit) differs from the folder (phy-cors-audit)
- 60Tools and files. Uses tools (web) that frontmatter does not declare
- 70When it triggers. States when to use, but not when not to
- 70Execution cost. Instruction body is 6382 tokens
- 100Steps. 8 steps
Everything here is measured from the skill text rather than judged by a model, so the numbers are checkable. A parameter weighs more when it is a more common reason for the process to stall.
Quality signals
- +4Description does not say when NOT to use the skill (false activations)
- +3Description length 829: 120–800 characters recommended
- +3Output format is not stated: the model decides each time
- +2Single-language instructions
- +5Description quotes 7 example trigger phrases
- +4Structure: 9 headings
- +3Step-by-step instructions: 8 items
- +4Has examples (12 code blocks)
- +1License stated
Quality base 70; lint remarks subtract, signals add up to 100. Result: 59.