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.
git clone --depth 1 https://github.com/markmhendrickson/foundationWrote 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.
[](https://agentmods.dev/rules/markmhendrickson/foundation/test_first_workflow)<a href="https://agentmods.dev/rules/markmhendrickson/foundation/test_first_workflow"><img src="https://agentmods.dev/badge/rules/markmhendrickson/foundation/test_first_workflow/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.
<a href="https://agentmods.dev/rules/markmhendrickson/foundation/test_first_workflow"><img src="https://agentmods.dev/badge/rules/markmhendrickson/foundation/test_first_workflow.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00023 | $0.01917 |
| Opus 5.5 | $0.00009 | $0.00767 |
| Sonnet 5.5 | $0.00005 | $0.00383 |
| Haiku 4.5 | $0.00002 | $0.00192 |
Grade A, and why
test_first_workflow 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.
How it starts
The opening of the file, as written. The whole thing — 341 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test-First Workflow Rules
Reference: Repository testing standards
Purpose
Enforces test-first (TDD) or test-alongside development workflow to catch bugs early and ensure comprehensive test coverage.
Scope
This document covers:
- Test-first workflow requirements
- Test writing alongside implementation
- Test execution before implementation verification
- Test coverage verification
This document does NOT cover:
- Test execution after implementation (see
agent_test_execution.mdc) - Test quality standards (see repository test quality rules)
Trigger Patterns
Agents MUST follow test-first workflow when:
- Implementing new features
- Adding new functions or methods
- Creating new API endpoints
- Building new UI components
- Adding new database operations
Test-First Workflow
Option 1: Pure TDD (Test-Driven Development)
For new features or significant changes:
-
Write test cases FIRST
- Create test file before implementation file
- Write test cases covering:
- Happy path
- Edge cases (null, empty, invalid values)
- Error cases
- Boundary conditions
-
Run tests to verify they fail (RED)
- Tests should fail because implementation doesn't exist
- This confirms tests are actually testing something
-
Implement feature to make tests pass (GREEN)
- Write minimal code to make tests pass
- Don't over-engineer
-
Refactor if needed (REFACTOR)
- Improve code quality while keeping tests green
- Verify tests still pass after refactoring
Option 2: Test-Alongside Development
For smaller changes or when TDD is impractical:
-
Write test cases alongside implementation
- Create test file at same time as implementation
- Write tests for each function as you implement it
- Don't defer test writing
-
Run tests frequently
- Run tests after each function implementation
- Fix failures immediately
- Verify tests pass before moving on
-
Ensure comprehensive coverage
- Test happy path
- Test edge cases
- Test error cases
- Verify all code paths covered
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.
- 1mo ago First seen · 341 lines · 23 tokens per session scan A 7dab94c97bb1
test_first_workflow is a cursor rule published in the GitHub repository markmhendrickson/foundation (2 stars, last pushed 2mo ago), licensed MIT. It adds 23 tokens to every session and 1,917 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-08-31.
Other cursor rules, from other repositories
mcpnuke-tests
Test conventions for mcpnuke — enforces TDD workflow.
debug-issue
When the user reports a bug, an error, or unexpected behavior. Enforces four structured phases — reproduction, failing test, root cause isolation, fix and verify — to stop guess-and-check loops.
common-testing
Testing requirements: 80% coverage, TDD workflow.
testing_rules
A testing guide covering TDD, where tests are written before code, and BDD, where expected behavior is described in Given-When-Then form.
tdd
Test-driven development — red-green-refactor cycle.
testing-standards
testing guidelines and expectations.