Manifest Reference

The Skill Manifest File is the JSON document that describes a skill: its name, version, license, the per-host materializations (targets) it ships, and optional dependency, taxonomy, and provenance metadata.

When a skill is registered onchain, the manifest's keccak256 hash is stored in manifestHashes(skillId) on the SkillRegistry. Clients fetch the manifest from tokenURI(skillId), verify that hash, then dereference and verify each target body against its declared integrity. Any byte-level change to the manifest invalidates the onchain commitment.

This page documents the schema implemented by asrpm. See the ERC-8239 specification for the normative definition.

Top-Level Fields

Field	Type	Required	Description
`type`	string	optional	Manifest type discriminator (e.g. `skill`)
`name`	string	recommended	Short, human-readable skill name. Used as the install directory name (sanitized).
`description`	string	recommended	One-line description of what the skill does
`image`	string	optional	URL to an icon or banner image
`version`	string	recommended	Semver string for this skill release
`license`	string	recommended	SPDX license identifier (e.g. `MIT`, `Apache-2.0`)
`keywords`	string[]	optional	Tags for discovery
`homepage`	string	optional	Project homepage URL
`repository`	string	optional	Source repository URL
`author`	Author	optional	Author identification
`targets`	Target[]	required	Per-host materializations of the skill
`requirements`	object	optional	Free-form host or runtime requirements
`taxonomy`	object	optional	Free-form classification metadata
`dependencies`	SkillReference[]	optional	Other skills this skill depends on
`supersedes`	SkillReference	optional	Skill this release supersedes
`status`	string	optional	Lifecycle status. `deprecated` triggers a client warning.

Unknown fields are tolerated by asrpm and ignored on unmarshal.

Target

A Target describes one way the skill is materialized for a particular host — a Claude Code SKILL.md, a Cursor rule, an MCP server, a CLI binary, etc. A skill manifest must include at least one target.

Field	Type	Required	Description
`kind`	string	required	Host identifier (e.g. `claude-code-skill`, `cursor-rule`, `mcp-server`). Clients pick a target by matching their host's expected kind.
`version`	string	optional	Per-target version, if it diverges from the manifest's `version`
`runtime`	string	optional	Runtime hint for the host (e.g. interpreter version)
`installation`	string	optional	Free-form installation notes for hosts that need them
`uri`	string	required	URI to the target body. Supported schemes: `https://`, `http://`, `data:`. (`ipfs://` is intentionally not supported.)
`integrity`	string	required	`<algorithm>:<hex>` digest of the body bytes (see Integrity Format)
`format`	string	optional	How to interpret the fetched content (default: `file`)

Target Kinds

asrpm v1 installs targets with kind = "claude-code-skill" into ~/.claude/skills/<name>/SKILL.md. Other kinds are recognized by the manifest format and may be referenced in dependency graphs, but writing them to disk is not yet implemented.

Author convention is to use a stable, hyphenated, host-prefixed identifier:

Kind	Description
`claude-code-skill`	Claude Code `SKILL.md` body
`cursor-rule`	Cursor rules file
`mcp-server`	Manifest pointing to an MCP server bundle
`cli-binary`	Pre-built CLI binary

The list is not normative — hosts and authors may define new kinds. asrpm matches by exact string equality on the configured --target flag.

Author

Field	Type	Required	Description
`name`	string	optional	Human-readable author name
`url`	string	optional	Author homepage
`agentId`	number	optional	ERC-8004 agent identifier, if the author is itself an onchain agent
`agentRegistry`	string	optional	Address of the agent registry, qualified with the chain (e.g. `eip155:1:0x...`)

SkillReference

A SkillReference points to another skill in the registry (or a different registry). Used by dependencies[] and supersedes.

Field	Type	Required	Description
`skillId`	number	required	Token ID of the referenced skill
`skillRegistry`	string	optional	Chain-qualified registry address (e.g. `eip155:11155111:0x8239…`). Defaults to the current registry.
`version`	string	optional	Pinned version of the referenced skill

Integrity Format

The integrity field uses an OCI-style algorithm-prefixed hex digest:

<algorithm>:<hex>

Algorithm	Notes
`keccak256`	Recommended for EVM-native skills; matches the `manifestHash` commitment algorithm
`sha256`	Recommended for interoperability with non-EVM tooling

Examples:

keccak256:97837f988678ef34cf4ea778f062a25e334d896d73bcf70bf81bfd7c9243f01e
sha256:4a8b1d8e3c2b6f5a0c9e1f2d3a4b5c6d7e8f9a0b1c2d3e4f5a6b7c8d9e0f1a2b

asrpm verifies the digest by recomputing the hash over the exact bytes returned from the target's URI and comparing to the declared value. Any mismatch aborts the install or verify operation.

URI Schemes

The manifest URI (written to tokenURI) and each target's uri must use one of the following schemes:

Scheme	Notes
`https://`	Recommended for hosted content. Subject to gateway availability.
`http://`	Supported but discouraged.
`data:`	Inline content (base64 or URL-encoded). Recommended for small bodies — the URI is self-contained and does not depend on a gateway.

The ipfs:// scheme is intentionally not supported by asrpm. Use the HTTPS gateway URL your pinning provider serves (e.g. https://gateway.pinata.cloud/ipfs/<cid>).

Status

The status field is a lifecycle marker. Recognized values:

Value	Effect
(unset)	Standard skill, no warning
`deprecated`	`asrpm` emits a warning before installing or invoking

Other values are tolerated but have no client-side effect.

Example Manifest

A minimal manifest with one claude-code-skill target served from a data: URI:

{
  "type": "skill",
  "name": "asrpm",
  "description": "Use the Agent Skill Registry (ERC-8239) to discover, install, and publish onchain agent skills.",
  "version": "0.1.0",
  "license": "MIT",
  "keywords": ["asr", "erc-8239", "agent-skill", "claude-code"],
  "homepage": "https://github.com/vorpalengineering/asrpm",
  "repository": "https://github.com/vorpalengineering/asrpm",
  "author": {
    "name": "Vorpal Engineering",
    "url": "https://vorpalengineering.com"
  },
  "targets": [
    {
      "kind": "claude-code-skill",
      "version": "0.1.0",
      "uri": "data:text/markdown;charset=utf-8;base64,LS0tCm5hbWU6IGFzcnBtCi4uLg==",
      "integrity": "keccak256:97837f988678ef34cf4ea778f062a25e334d896d73bcf70bf81bfd7c9243f01e",
      "format": "file"
    }
  ]
}

A manifest with multiple targets and dependencies:

{
  "name": "example-skill",
  "version": "1.2.0",
  "license": "Apache-2.0",
  "author": {
    "name": "Example Author",
    "agentId": 42,
    "agentRegistry": "eip155:1:0xAgentRegistry..."
  },
  "targets": [
    {
      "kind": "claude-code-skill",
      "uri": "https://example.com/skill.md",
      "integrity": "keccak256:abc123...",
      "format": "file"
    },
    {
      "kind": "cursor-rule",
      "uri": "https://example.com/rule.mdc",
      "integrity": "sha256:def456...",
      "format": "file"
    }
  ],
  "dependencies": [
    {
      "skillId": 0,
      "skillRegistry": "eip155:11155111:0x8239AAbaa1A44338bEeFAAf4C3a373d2a18D5DC4",
      "version": "^0.1.0"
    }
  ],
  "supersedes": {
    "skillId": 17,
    "version": "1.1.0"
  }
}

Authoring Tips

The manifest URI must serve byte-identical content to the local file you hashed. Any change — trailing newline, key reordering, whitespace — invalidates the onchain commitment and causes integrity verification to fail for downstream clients.
Prefer data: URIs for small manifests and target bodies. They are self-contained and avoid gateway availability issues.
When hosting on IPFS, register the gateway HTTPS URL (e.g. https://gateway.pinata.cloud/ipfs/<cid>) rather than ipfs://<cid>. Integrity verification works regardless of gateway choice.
Use the asrpm-prepare.sh helper to handle the body-encoding, hashing, and manifest-splicing steps in one pass.

Top-Level Fields​

Target​

Target Kinds​

Author​

SkillReference​

Integrity Format​

URI Schemes​

Status​

Example Manifest​

Authoring Tips​

See Also​