header-injection

HTTP header injection — CRLF/response splitting, Host-header cache poisoning, X-Forwarded-* abuse, Content-Disposition/Set-Cookie injection, and password-reset link poisoning via unvalidated header values.

Quality

78%

Does it follow best practices?

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Securityby

Critical

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tessl review fix ./packages/decepticon/decepticon/skills/standard/exploit/web/header-injection/SKILL.md

Quality

Content

82%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A dense, highly actionable offensive-testing playbook with executable curl commands, payload tables, and explicit verification signals across each header-injection class. It is slightly verbose in places and monolithic — everything lives inline in SKILL.md with no reference files — but the structure and verification checkpoints are strong.

Suggestions

Move the CR/LF payload table and the per-technique exploitation details into a references/ file (e.g. PAYLOADS.md) referenced one level deep, keeping SKILL.md as a tighter overview.

Tighten the intro paragraph and a few payload-table 'Notes' cells to remove explanation Claude can infer, improving token efficiency.

Add an explicit end-to-end workflow ordering (e.g. enumerate attack surface → pick technique → probe → verify win signal → record evidence) at the top so the parallel sections read as a sequenced process.

Dimension	Reasoning	Score
Conciseness	The body is largely efficient and assumes Claude's HTTP knowledge, with a brief load-bearing intro and tight per-technique curl snippets; a few explanatory asides in the payload table and intro could be trimmed slightly, so it sits just below the 'lean and efficient' anchor.	4 / 5
Actionability	Every technique section provides copy-paste-ready curl commands with concrete payloads, header injection strings, and grep-based 'win signal' criteria covering the common cases.	5 / 5
Workflow Clarity	A Verification Checklist with explicit per-technique checkpoints, win signals, and a cache-poisoning confirm loop provides clear validation; it falls short of 5 because the skill is organized as parallel technique categories rather than one fully sequenced workflow with end-to-end feedback loops.	4 / 5
Progressive Disclosure	Content is well-structured with clear section headers and no nested references, and no bundle files exist to split out; it is not a 5 because the payload table and per-technique playbooks are entirely inlined with no one-level-deep reference files for the larger material.	4 / 5
	Total	17 / 20 Passed

Description

75%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A specific, well-scoped description that enumerates concrete header-injection sub-techniques and would not collide with other skills. Its main weakness is the absence of an explicit 'Use when...' clause, which leaves the triggering context implicit and caps completeness.

Suggestions

Add an explicit 'Use when...' clause to the description, e.g. 'Use when testing for CRLF/response splitting, host header poisoning, cache poisoning, or password-reset link hijacking.'

Surface a couple of the most common user-facing synonyms (e.g. 'response splitting', 'HTTP response splitting') directly in the description rather than only in metadata.when_to_use.

Dimension	Reasoning	Score
Specificity	The description lists multiple concrete sub-techniques — 'CRLF/response splitting', 'Host-header cache poisoning', 'X-Forwarded-* abuse', 'Content-Disposition/Set-Cookie injection', and 'password-reset link poisoning' — giving comprehensive coverage rather than vague abstraction.	5 / 5
Completeness	The 'what' is explicit and concrete, but the description lacks an explicit 'Use when...' trigger clause; per the rubric guideline, a missing explicit trigger clause caps completeness at 3 even when the what is clear.	3 / 5
Trigger Term Quality	It surfaces natural terms a security tester would say ('CRLF/response splitting', 'host header poisoning', 'password-reset link poisoning') with synonyms, but is missing a few common variations like 'response splitting' phrased alone and file-extension-style triggers; the bulk of synonyms live in metadata.when_to_use rather than the description itself.	4 / 5
Distinctiveness Conflict Risk	It carves a clear niche (HTTP header injection) with technique-specific triggers, making it unlikely to fire for unrelated skills.	5 / 5
	Total	17 / 20 Passed

Validation

93%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
metadata_version	'metadata.version' is missing	Warning

	Total	15 / 16 Passed

Repository: PurpleAILAB/Decepticon
Path: packages/decepticon/decepticon/skills/standard/exploit/web/header-injection/SKILL.md
Commit: 0cf691e

Reviewed: 2 days ago

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