state-memory-mcp: Skill for Claude Code

.agents/skills/webcrypt-mcp/SKILL.md

webcrypt-mcp is a skill for Claude Code, Codex from putervision/state-memory-mcp. It costs 58 tokens per session (945 once invoked), scanned A, original, MIT.

An agent skill for using WebCrypt to encrypt data, create keys, make digital signatures, and calculate hashes. It also covers public-key encryption and post-quantum cryptography, which is designed to resist attacks from future quantum computers.

In plain words
What is it for?
It is for encrypting payloads, generating keys, signing evidence or release files, checking signatures, and producing HMAC tags.
Why use it?
It gives agents defined steps for protecting credentials, private workflow data, caches, and other sensitive outputs before storing or sharing them.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

This is putervision/state-memory-mcp's own configuration. It tells Claude Code and Codex how to work on state-memory-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything state-memory-mcp configures →

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is node .agents/skills/webcrypt-mcp/scripts/exercise_tools.js.

Reuse

Borrowing it

Nothing to install: this file belongs to putervision/state-memory-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/putervision/state-memory-mcp/main/.agents/skills/webcrypt-mcp/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/putervision/state-memory-mcp

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for webcrypt-mcp

README.md
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Your own site
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Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for webcrypt-mcp

Your own site · 80×15
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Per session 58 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 945 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00058 $0.00945
Opus 5.5 $0.00023 $0.00378
Sonnet 5.5 $0.00012 $0.00189
Haiku 4.5 $0.00006 $0.00094

Measured 1mo ago against content hash fdee92b6c05c, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

webcrypt-mcp scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

.agents/skills/webcrypt-mcp/SKILL.md · 39 lines

How it starts

The opening of the file, as written. The whole thing — 39 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Cryptographic Memory & Vault Tooling (webcrypt-mcp)

This project provides webcrypt-mcp, a native Model Context Protocol server for zero-dependency AES-256-GCM encryption, RSA-4096 hybrid public-key encryption, digital signatures, cryptographic hashes, and post-quantum cryptography.

1. Mandatory Workflow & Priority

  1. Confidential Artifacts: Whenever saving sensitive credentials, tokens, or private workflow states, encrypt them using encrypt_payload(mode: "data", password: "...") or encrypt_payload(mode: "symmetric", password: "...").
  2. Key Management: Use manage_keys(action: "generate", type: "rsa" | "ecdh" | "ecdsa" | "rsa-pss" | "hmac") to generate cryptographically strong JWK-formatted keys for inter-agent communication.
  3. Integrity & Signatures: Before completing tasks that produce verifiable evidence (such as evidence packs or release binaries), compute signatures or HMAC tags using sign_verify(action: "sign", algorithm: "ECDSA" | "HMAC").
  4. Triple Memory Triad:
    • state-memory-mcp: Workflow state tracking.
    • vision-memory-mcp: Visual state caching.
    • webcrypt-mcp: Encryption of sensitive DAG nodes, visual cache database vaults, and signature verification.

2. Complete Tool Reference

Tool Name Key Inputs Description
encrypt_payload mode ('symmetric' | 'asymmetric' | 'data'), data, password?, public_key_jwk? Encrypt plaintext, JSON object, or binary data.
decrypt_payload mode ('symmetric' | 'asymmetric' | 'data'), ciphertext, password?, private_key_jwk? Decrypt ciphertext back to plaintext or structured JSON.
manage_keys action ('generate' | 'generate_random_password'), type ('rsa' | 'ecdh' | 'ecdsa' | 'rsa-pss' | 'hmac'), modulusLength?, namedCurve?, length? Generate cryptographic keys (JWK format) or secure random passwords.
crypto_hash algorithm ('SHA-256' | 'SHA-384' | 'SHA-512' | 'SHA3-256' | 'SHA3-512'), data, encoding ('hex' | 'base64') Compute cryptographic hash digests.
sign_verify action ('sign' | 'verify'), algorithm ('ECDSA' | 'RSA-PSS' | 'HMAC' | 'HMAC-SHA3'), data, signature?, password?, key_jwk? Sign or verify messages with ECDSA, RSA-PSS, or HMAC.
pqc_kem_sign action ('generate_kyber_keypair' | 'kyber_encapsulate' | 'kyber_decapsulate' | 'hybrid_encapsulate' | 'hybrid_decapsulate' | 'generate_dilithium_keypair' | 'dilithium_sign' | 'dilithium_verify'), level?, public_key_b64?, private_key_b64?, ... Post-quantum Kyber KEM, Dilithium signatures, and Hybrid KEM.

Read the full file on GitHub · 39 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 1mo ago First seen · 39 lines · 58 tokens per session scan A fdee92b6c05c

Subscribe to this mod's changes

webcrypt-mcp is a skill published in the GitHub repository putervision/state-memory-mcp (42 stars, last pushed 1mo ago), licensed MIT. It adds 58 tokens to every session and 945 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-11.

Related

webcrypt-mcp compared with skills from other repositories

webcrypt-mcp next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
webcrypt-mcpputervision/state-memory-mcpSkill421mo agoMITA58Claude Code, Codex
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cortex-explore-memorycdeust/CortexSkill76todayMITA91Claude Code
qmclaw-workbenchxi-zhao/OpenQuantumSkill71todayMITA124Codex
quantum-groverxi-zhao/OpenQuantumSkill71todayMITA62Claude Code, Codex
quantum-algorithmsxi-zhao/OpenQuantumSkill71todayMITA34Claude Code, Codex
alicebob-cat-circuitsxi-zhao/OpenQuantumSkill71todayMITA51Claude Code, Codex