BC content-security-filter
Prompt injection and malware detection filter for external content. Scans text, files, or URLs for 20+ attack patterns including instruction overrides, credential exfiltration, persona hijacking, encoded payloads, fake system messages, and invisible character injection. Returns JSON with risk level and sanitized text.
As a process C 60/100 · Has gaps — weak spots: when it triggers, failures and branches, running it twice
How to improve
- Say in the description WHEN to use the skill ("use when…", example requests): that is the agent's main cue.
- 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 · 5
✓ No critical or high findings
Medium and low: 5
-
low Instruction override
en-ignore-previousSKILL.md:14Instruction-override phrase ("ignore previous instructions") (documentation table row; documentation of a security skill)| Override attempts | "ignore previous instructions", "forget everything" |
tablesecurity skill -
low Risky intent
intent-offensive-securitySKILL.md:22Offensive-security / dual-use content (legitimate for authorised testing; review intended use)| Credential harvesting | "provide your password/token/secret" |
A further 3 matches are quotations in this security skill's documentation and are not counted as findings.
Files scanned: 3. Evidence is masked. Grey chips explain why severity was lowered.
Against the Agent Skills spec
- warning
description-no-whendescription does not say WHEN to use the skill (no "use when")
Process rating: all ten parameters 60/100
- 0Failures and branches. Linear process with no failure handling
- 0Progress reporting. Says nothing while it works
- 20When it triggers. No condition that starts the skill
- 30Running it twice. 1 mutating operations with no state check
- 60Tools and files. Uses tools (python) that frontmatter does not declare
- 60Result and completion. Output format stated, no completion criterion
- 70Inputs and preconditions. Inputs and preconditions are listed
- 100Steps. 6 steps
- 100Consistency. Name and required fields are in place
- 100Execution cost. Instruction body is 569 tokens
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
- +5Description has no quoted example phrases that should trigger the skill
- +4Description does not say when NOT to use the skill (false activations)
- +1No license
- +2Single-language instructions
- +3Description length 319: enough signal without eating the budget
- +4Structure: 6 headings
- +3Step-by-step instructions: 6 items
- +3Output format is stated explicitly
- +4Has examples (2 code blocks)
- +3All 1 scripts are documented
Quality base 70; lint remarks subtract, signals add up to 100. Result: 78.