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The "Cloudflare for AI Agents". 7-layer security interceptor, real-time observability dashboard, and automated reliability testing for MCP and AI tool chains. Prevent hallucinations, prompt injection, and destructive tool calls.

14 starsPython

ToolGuard – Pytest for AI agent tool calls

by Heer_J·Mar 17, 2026·1 point·0 comments
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AI Analysis

●●●BangerShip ItSolve My ProblemBig Brain

Layer 2 execution testing without LLMs when eval frameworks only test intelligence.

Strengths
  • •Separates execution reliability from intelligence evals — genuinely useful framing for agent developers
  • •Deterministic fuzzing from type hints means no LLM needed to run the tests themselves
  • •Reliability score with deploy block recommendations gives clear go/no-go signals
Weaknesses
  • •Very early with only 16 commits and 1 star — needs more real-world validation
  • •Python-only support limits adoption for teams using other agent frameworks
Target Audience

AI agent developers building Python tool chains

Similar To

LangSmith evals · Pytest · Hypothesis

Post Description

I got tired of my AI agents crashing because the LLM hallucinated a JSON key or passed a string instead of an int. So I built ToolGuard — it fuzzes your Python tool functions with edge-cases (nulls, missing fields, type mismatches, 10MB payloads) and gives you a reliability score out of 100%.

No LLM needed to run tests. It reads your type hints, generates a Pydantic schema, and deterministically breaks things.

pip install py-toolguard

GitHub: https://github.com/Harshit-J004/toolguard

If you are building complex tool chains, I would be incredibly honored if you checked out the repo. Brutal feedback on the architecture is highly encouraged!

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