Daml Skill for Claude

A Claude skill that gives any Claude/ Claude Code conversation correct knowledge of the Daml smart contract and Canton Network. Useful for developers writing, reviewing, or debugging Daml contracts.

What it does

When you ask Claude about Daml templates, choices, authorization errors, multiparty workflows, testing with Daml Script, SDK setup, Canton 3.5 changes, the skill loads automatically and guides Claude to give correct, grounded answers rather than plausible-sounding guesses.

Installation

1. Download this repo in .zip file from code tab in top right.
2. In Claude, go to Customize → Skills
3. Upload the .zip file
4. Refresh/ Restart Claude then in a new conversation the skill is now active.

What it's good at

Catching authorization errors before they hit the ledger

The most common Daml failure mode isn't a syntax error it's an authorization chain that doesn't add up. The skill traces who needs to authorize what, and whether the parent transaction covers it.

Naming the right pattern

Instead of improvising a workflow from scratch, the skill recognizes when Propose Accept, Delegation, or Multiple Party Agreement is the right structure, and gives you a correct skeleton rather than a plausible-looking one.

createCmd vs create and other context-dependent syntax

createCmd is only valid inside submit blocks in Daml Script. create is only valid inside choice do blocks. This trips up almost everyone new to Daml. The skill catches this and corrects it.

Canton 3.5 / SDK 3.5 specifics

The daml CLI is removed in SDK 3.5. Contract keys require --target=2.3. daml-script must not appear in production packages. Scope-based JWTs are deprecated. The skill knows all of this and applies it when relevant.

Code review

Paste a Daml file and ask for a review. The skill works through a checklist: module header, signatories, authorization chain, ensure clauses, choice return types, consuming/non-consuming correctness, Cmd suffix usage, test coverage.

What it won't do

• It won't write your entire application for you without understanding the business logic
• It won't make authoritative claims about undocumented or rapidly-changing Canton Network APIs (it will say so)
• It won't replace running dpm test always test your code

Triggers

The skill activates on questions about:

• Daml templates, choices, signatories, observers, controllers
• Authorization errors and why a transaction fails
• Daml Script tests (submit, submitMustFail, queryContractId, etc.)
• Multi-party workflows and which pattern to use
• daml.yaml configuration and project structure
• dpm commands (build, test, studio, sandbox, codegen)
• Contract keys, interfaces, data types
• Canton 3.5 / SDK 3.5 migration
• Translating Ethereum/Solidity patterns to Daml