foundry

foundry is a skill for Claude Code from sablier-labs/plugin-marketplace. It costs 49 tokens per session (1,917 once invoked), scanned A, a copy of cli-forge, MIT.

A guide for writing Foundry tests and deployment scripts for Solidity smart contracts. Foundry is a toolkit for building, testing, deploying, and measuring blockchain contracts.

In plain words
What is it for?
Use it for integration, fuzz, fork, and invariant tests, deployment scripts, gas benchmarks, code coverage, and formal verification.
Why use it?
It provides project-specific patterns for different test types and common testing tools, so developers do not have to invent their own structure.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the testing plugin — 3 skills shipped together

Good fit Use it for integration, fuzz, fork, and invariant tests, deployment scripts, gas benchmarks, code coverage, and formal verification.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/sablier-labs/plugin-marketplace/foundry
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 sablier-labs/plugin-marketplace --skill foundry
Clone the repo
git clone --depth 1 https://github.com/sablier-labs/plugin-marketplace

Made for: Claude Code.

Or install testing, the plugin that ships this one along with the rest of its 3 skills.

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 foundry

README.md
[![agentmods](https://agentmods.dev/badge/skills/sablier-labs/plugin-marketplace/foundry/github.svg)](https://agentmods.dev/skills/sablier-labs/plugin-marketplace/foundry)
Your own site
<a href="https://agentmods.dev/skills/sablier-labs/plugin-marketplace/foundry"><img src="https://agentmods.dev/badge/skills/sablier-labs/plugin-marketplace/foundry/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 foundry

Your own site · 80×15
<a href="https://agentmods.dev/skills/sablier-labs/plugin-marketplace/foundry"><img src="https://agentmods.dev/badge/skills/sablier-labs/plugin-marketplace/foundry.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 49 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,917 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 97% copy Near-identical to another mod 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 $0.00049 $0.01917
Opus 5.5 $0.00020 $0.00767
Sonnet 5.5 $0.00010 $0.00383
Haiku 4.5 $0.00005 $0.00192

Measured 1mo ago against content hash febb52b6c228, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

foundry 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

This is a copy

97% identical to cli-forge — 2 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/testing/skills/foundry/SKILL.md · 240 lines

How it starts

The opening of the file, as written. The whole thing — 240 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Foundry Testing & Script Skill

Rules and patterns for Foundry tests. Find examples in the actual codebase.

Bundled References

Reference Content When to Read
./references/test-infrastructure.md Constants, defaults, mocks When setting up tests
./references/cheat-codes.md Common cheatcode patterns When using vm cheatcodes
./references/invariant-patterns.md Handlers, stores, invariants When writing invariant tests
./references/formal-verification.md Halmos, Certora, symbolic exec When proving correctness
./references/deployment-scripts.md Script patterns, verification When writing deploy scripts
./references/deployment-checklist.md Pre-mainnet deployment steps Before deploying to production
./references/gas-benchmarking.md Snapshot, profiling, CI When measuring gas performance
./references/sablier-conventions.md Sablier-specific patterns When working in Sablier repos

Test Types

Type Directory Naming Purpose
Integration tests/integration/concrete/ *.t.sol BTT-based concrete tests
Fuzz tests/integration/fuzz/ *.t.sol Property-based testing
Fork tests/fork/ *.t.sol Mainnet state testing
Invariant tests/invariant/ Invariant*.t.sol Stateful protocol properties
Scripts scripts/solidity/ *.s.sol Deployment/initialization

Read the full file on GitHub · 240 lines

Files

What ships with it

8 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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 · 240 lines · 49 tokens per session scan A febb52b6c228

Subscribe to this mod's changes

foundry is a skill published in the GitHub repository sablier-labs/plugin-marketplace (7 stars, last pushed 13d ago), licensed MIT. It adds 49 tokens to every session and 1,917 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 97% identical to cli-forge, differing in 2 lines, and is treated as a copy.

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