350,000 Skills, Zero Cryptographic Trust — Introducing MT Skill Verification

The Skill Explosion

AI agent skills — small, composable units of capability that agents load at runtime — have become the building blocks of the agent economy. SkillsMP alone hosts over 350,000 skills, with SkillHub contributing another 7,000+. The growth rate is staggering: 10x year-over-year, with no sign of slowing down.

Agents don't install skills like traditional software. They fetch them at runtime from URLs — a SKILL.md file describing what the skill does, what tools it uses, and how to invoke it. There is no compilation step. No build pipeline. No review board. A skill published at 2:00 PM can be running inside a thousand agents by 2:01 PM.

The problem: none of this is verified. No hashing. No signatures. No integrity checks. It's the equivalent of installing npm packages without a lockfile — except the packages are executable prompts running inside agents with tool access.

What Can Go Wrong

When skills have no cryptographic identity, every agent that loads one is making a trust assumption that cannot be verified. Here are the four categories of risk we identified:

Traditional software has package managers with checksums, code signing, and vulnerability databases. The AI skill ecosystem has none of this. MT Skill Verification fills that gap.

How MT Skill Verification Works

The verification pipeline is designed to be simple, deterministic, and cryptographically anchored at every step.

Submit a skill URL. MoltGuard fetches the SKILL.md, runs an automated 8-point security audit, scores it 0–100, and — if it passes — issues a VerifiedSkillCredential binding the author, the content hash, and the audit results into a W3C Verifiable Credential.

The Canonical Hash

Verification starts with identity, and for a skill, identity is its content. But content can vary in invisible ways — BOM markers, line endings, trailing whitespace, Unicode normalization forms. Two files that look identical can produce different hashes.

MT Skill Verification solves this with the SKILL_HASH_SPEC — a deterministic normalization pipeline:

• Strip BOM — remove UTF-8 byte order mark if present
• Normalize line endings — convert \r\n and \r to \n
• Trim whitespace — strip trailing whitespace from every line
• Collapse blanks — reduce consecutive blank lines to a single blank line
• NFC normalize — apply Unicode NFC normalization
• SHA-256 — hash the normalized content

This is the foundation everything else builds on. The hash is the skill's fingerprint. It goes into the Verifiable Credential, into the audit record, and into the verification endpoint. Same content produces the same hash. Always. Any change — even a single added space — produces a different hash, and verification fails.

The 8-Point Security Audit

Every skill submitted for verification goes through an automated audit that checks eight dimensions of safety and quality. Each check has a severity level and a point deduction if it fails.

Every skill starts at 100 points. Deductions are applied for each failed check. The passing threshold is 70/100 — skills below this score do not receive a VerifiedSkillCredential. The full breakdown is returned in the audit response so authors can fix issues and resubmit.

The audit is deterministic: the same content always produces the same score. No LLM randomness. No subjective judgment. Pattern matching and static analysis only.

VerifiedSkillCredential

Skills that pass the audit receive a VerifiedSkillCredential — a W3C Verifiable Credential that cryptographically binds the skill's identity to its audit results.

The credential encodes:

• Author DID — the skill author's decentralized identifier
• Skill hash — the canonical SHA-256 hash of the SKILL.md content
• Audit score — the 0–100 score from the 8-point audit
• Audit details — which checks passed and which failed
• Timestamp — when the audit was performed
• Validity period — 90 days from issuance

Every credential is signed with Ed25519 using JWS compact serialization. It can be verified by hash (does this exact content have a valid credential?) or by DID (has this author's skill been verified?).

API Endpoints

MT Skill Verification exposes three core endpoints. All are free during Early Access.

Audit a Skill

Verify a Skill

Issue a VerifiedSkillCredential

Full API documentation is available at /skill/info.

What's Next

MT Skill Verification is live today, but this is the beginning. Here's the roadmap:

• Integration with major skill marketplaces — SkillsMP, SkillHub, and other platforms can embed verification badges and reject unverified skills at the registry level.
• Automated re-audit on content changes — webhook-triggered re-verification when a skill's SKILL.md is updated, with automatic credential revocation if the new version fails.
• Reputation scoring for skill authors — aggregate VC history into an author trust score. Authors who consistently publish clean, verified skills build reputation. Authors with revocations lose it.

The agent economy cannot scale on blind trust. Every skill loaded at runtime is an attack surface. MT Skill Verification makes that surface auditable, hashable, and cryptographically verifiable.

MT Skill Verification is built by MolTrust (CryptoKRI GmbH, Zurich) — trust infrastructure for the agent economy. Follow @MolTrust on X for updates.