Skill Claude CodeCodex
Hunt the bugs that live where two components read the same bytes and disagree about what they mean — the validator parses one way, the executor another, and the attacker writes input that is two things at once. Use whenever a value crosses a component, language, or process boundary and is re-interpreted — proxy in…
Skill Claude CodeCodex
Treat the CI/CD pipeline as a privileged execution environment that runs attacker-influenceable code with production credentials — not as configuration — because a build step is arbitrary code execution holding the keys to deploy, and the pipeline sits inside your trust boundary while rarely being modeled as an attack…
Skill Claude CodeCodex
Run an AUTHORIZED, collaborative purple-team exercise — turn each attack technique into a detection hypothesis, detonate it minimally and marked, and measure whether the blue side prevented it, detected it, or missed it entirely. Use this whenever the user wants to validate detection coverage, test whether a control…
Skill Claude CodeCodex
Treat a backup you have not proven restorable and untampered as a hope, not a recovery plan — because the backup is inside the blast radius (same domain credentials, same network, same admin), and ransomware operators delete or encrypt backups before they detonate, so "we have backups" answers a question you did not…
Skill Claude CodeCodex
Adversarial security auditing and red-teaming of your own systems with strict epistemic discipline. Use this skill whenever the user is red-teaming, doing a security audit, adversarial review, threat modeling, or "trying to break" their own code or system; whenever they ask you to find bugs, vulnerabilities, invariant…
Skill Claude CodeCodex
Write the report that actually gets the class fixed — survivable in a triage queue of forty, severity scored to the demonstrated impact instead of inflated, framed so that closing your instance does not close the underlying pattern, and followed through until the patch is verified against the class and not merely…
Skill Claude CodeCodex
Find the places in your own code where a small input buys a large amount of work or memory, and bound them — input-controlled loops and allocations, super-linear algorithms, catastrophic regex backtracking, decompression and expansion ratios, unbounded fan-out and retries, and missing backpressure. Use whenever…
Skill Claude CodeCodex
Reconstructing how an undocumented, closed, or unfamiliar system works when you do NOT have its design — a binary, a network protocol, a file or wire format, an undocumented or third-party API, a firmware image, a memory dump, an opaque database, or a model whose behavior you can only infer from inputs and outputs.…
Skill Claude CodeCodex
Reason about integrity you cannot verify from inside the thing you are verifying — a compromise below your vantage point is invisible because it controls what you see, so a bootkit that owns UEFI or SPI flash shows a spotless OS to every OS-level scanner, and trust must be anchored to a root below the layer that could…
Skill Claude CodeCodex
Treat credentials as a lifecycle — issued, scoped, distributed, used, rotated, revoked — with redaction enforced at the boundary and rotation rehearsed before it is needed. Use whenever a secret is created, read, passed, logged, printed, committed, or exposed: API keys, tokens, passwords, private keys, connection…
Skill Claude CodeCodex
Deliberate, security-first software construction that assumes a hostile user rather than an ideal one. Use this skill whenever code is being designed, written, extended, refactored, or reviewed before merge — features, endpoints, APIs, parsers, auth, file/DB/network/subprocess handling, schemas, architecture decisions…
Skill Claude CodeCodex
Reason about attacks that exploit human trust rather than a software flaw — where the target made a locally reasonable decision on deliberately crafted context, and no patch fixes it because the "vulnerability" is a person doing their job. Use whenever the vector is a human: "was this phishing", "how did they fall for…
Skill Claude CodeCodex
Do not stop at a reproducible symptom — the gate that makes you earn the report before writing it. Name the broken invariant and its layer, sweep for variants, attack the fix you expect the maintainer to ship, map the real blast radius across shipped clients and versions, and calibrate severity against a named…
Skill Claude CodeCodex
Disciplined modification of existing, legacy, inherited, or unfamiliar code — change without breakage, deletion without regret. Use this skill whenever the user asks to modify, refactor, clean up, simplify, modernize, migrate, or delete existing code; fix a bug in code they (or you) did not write; upgrade a dependency…
Skill Claude CodeCodex
Push counting, summing, and grouping into the database instead of loading rows to tally them in application code; replace per-item queries inside loops with one batched query; and cap any result set that can grow without bound. Use this whenever code reads from a database to compute a statistic, whenever a loop issues…
Skill Claude CodeCodex
Apply changes to existing source files by anchored, verified, reversible patches instead of rewriting whole files. Use this whenever you are about to edit, refactor, or modify an existing file programmatically; when applying a patch, diff, or change set proposed by an auditor or another model; when doing…
Skill Claude CodeCodex
Build and verify append-only logs that prove no entry was altered, inserted, reordered, or dropped after the fact — a hash chain where each entry seals the previous one. Use this whenever you build or review an audit trail, ledger, chain of custody, provenance record, or any append-only log that could later be…
Skill Claude CodeCodex
Resist the pull to name an actor — attribution is the most overinterpreted act in security, and every signal that points at APT-X (shared hash, reused C2, a Cyrillic string, a compile timezone) is evidence of contact between datasets, not identity of hands, and most of it is cheap to plant. Use whenever an…
Skill Claude CodeCodex
Read network traffic as evidence to be interpreted under two hard limits — you usually cannot see the payload (encryption) and rare is usually benign (base rates) — never as a verdict on its own; beaconing, JA3/JA4 fingerprints, timing, volume, and destination reputation are weak signals whose meaning lives in…
Skill Claude CodeCodex
Get determinism in machine learning where it is actually achievable — the artifact, not the process — by pinning data version, materialized split, code, resolved config, environment and hardware into a sealed manifest, naming the irreducibly nondeterministic parts instead of pretending they are absent, and labeling…
Skill Claude CodeCodex
Hunt the gap between the features a model was trained on and the features it is actually served — two implementations of one computation, a value that is complete offline and partial online, preprocessing shipped separately from the model, and the silent default that fills in a failed feature so the model answers…
Skill Claude CodeCodex
Examine a hostile artifact as what it is — a live adversary you invited onto your desk — with two invariants: never let it execute where it can reach anything real, and never confuse what it CAN do (capability) with what it DID or was aimed at (intent). Use whenever a suspicious binary, script, document, archive, APK…
Skill Claude CodeCodex
Validate untrusted inputs at the edge of the system — with a clear error raised at the boundary — instead of letting bad shape, bad dtype, non-finite values, or hostile paths explode deep inside a library or propagate as silent corruption. Use this whenever code ingests data from outside its own control — deserialized…
Skill Claude CodeCodex
Turn one disclosed or found bug into a family: extract the violated invariant, hunt the same class across shared deps and sibling sinks, and check dedupe/fix-coverage before filing.
At most 3 mods per repository are shown here, and a mod shipped inside a plugin is left to that plugin's page — the rest are on their repository pages: