tx-safety

tx-safety is a skill for Claude Code from lidonation/Cardano-mcp. It costs 50 tokens per session (657 once invoked), scanned A, original, MIT.

A safety check for building and submitting Cardano blockchain transactions, including confirming the network and transaction details before funds move.

In plain words
What is it for?
Use it before building or broadcasting payment or smart-contract transactions, especially when distinguishing Cardano mainnet from a test network and confirming ADA or token details.
Why use it?
Blockchain submissions cannot be undone, and the wrong network, recipient, or amount can move real assets permanently.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the cardano-verify plugin — 2 skills, 1 MCP server shipped together

Good fit Use it before building or broadcasting payment or smart-contract transactions, especially when distinguishing Cardano mainnet from a test network and confirming ADA or token details.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/lidonation/cardano-mcp/tx-safety
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add lidonation/Cardano-mcp --skill tx-safety
Clone the repo
git clone --depth 1 https://github.com/lidonation/Cardano-mcp

Made for: Claude Code.

Or install cardano-verify, the plugin that ships this one along with the rest of its 2 skills, 1 MCP server.

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 tx-safety

README.md
[![agentmods](https://agentmods.dev/badge/skills/lidonation/cardano-mcp/tx-safety/github.svg)](https://agentmods.dev/skills/lidonation/cardano-mcp/tx-safety)
Your own site
<a href="https://agentmods.dev/skills/lidonation/cardano-mcp/tx-safety"><img src="https://agentmods.dev/badge/skills/lidonation/cardano-mcp/tx-safety/github.svg" alt="Measured on agentmods" height="20"></a>

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 tx-safety

Your own site · 80×15
<a href="https://agentmods.dev/skills/lidonation/cardano-mcp/tx-safety"><img src="https://agentmods.dev/badge/skills/lidonation/cardano-mcp/tx-safety.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 50 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 657 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 $0.00050 $0.00657
Opus 5 $0.00025 $0.00329
Sonnet 5 $0.00010 $0.00131
Haiku 4.5 $0.00005 $0.00066

Measured today against content hash 4fe042e621b8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-22, from the pricing page.

Security

Grade A, and why

tx-safety 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 today.

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.

plugins/cardano-verify/skills/tx-safety/SKILL.md · 48 lines

How it starts

The opening of the file, as written. The whole thing — 48 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Transaction safety guardrail

submit_transaction broadcasts a signed transaction to the real network. Nothing about the tool itself stops it from running against mainnet with the wrong amount, the wrong recipient, or while the user believed they were on a testnet. Once a transaction lands on-chain it cannot be undone. Treat every call to submit_transaction — and the build_* calls that precede it — as irreversible until proven otherwise.

Workflow

  1. Before building any transaction, call get_network_info. Do not assume the network from context, prior conversation, or what the user "probably" meant.
  2. State the active network out loud to the user before proceeding, plainly — not buried in a JSON blob. If is_mainnet is true, say so explicitly: this transaction will move real ADA/assets.
  3. After building a transaction (build_payment_tx or build_smart_contract_tx), before calling submit_transaction, restate to the user in plain language: the network, the sender, the recipient, the exact amount (in ADA, not just lovelace), and any native assets. This restatement must happen even if the user already stated these values earlier in the conversation — confirm what the built transaction actually contains, not what was requested.
  4. Get an explicit go-ahead from the user in the current turn before calling submit_transaction — a prior "yes, build it" is not the same as confirmation to submit. If the user has not responded to the restatement yet, stop and wait; do not call submit_transaction speculatively.
  5. If get_network_info reports mainnet and the user has not clearly indicated they intend to use mainnet (e.g. they only ever mentioned "testnet" or "preprod"), flag the mismatch and ask before continuing rather than proceeding on the assumption they meant mainnet.

Why this exists

The eUTxO model has no reversible "undo" — a submitted transaction is final once confirmed, and a testnet/mainnet mix-up or a mistyped amount has real financial consequences. A model's confidence that it has the right sender, recipient, and network is not the same as verifying it — this skill forces that verification through get_network_info and an explicit human confirmation step, the same way aiken-verify forces compiler verification before showing Aiken code as correct.

Read the full file on GitHub · 48 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. today First seen · 48 lines · 50 tokens per session scan A 4fe042e621b8

Subscribe to this mod's changes

tx-safety is a skill published in the GitHub repository lidonation/Cardano-mcp (2 stars, last pushed yesterday), licensed MIT. It adds 50 tokens to every session and 657 once invoked, about $0.0003 per session on Opus 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 2026-09-21.