Borrowing it
Nothing to install: this file belongs to rjmurillo/ai-agents. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/rjmurillo/ai-agents/main/.github/instructions/pragmatic-programmer.instructions.mdgit clone --depth 1 https://github.com/rjmurillo/ai-agentsWrote 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/instructions/rjmurillo/ai-agents/pragmatic-programmer)<a href="https://agentmods.dev/instructions/rjmurillo/ai-agents/pragmatic-programmer"><img src="https://agentmods.dev/badge/instructions/rjmurillo/ai-agents/pragmatic-programmer/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/instructions/rjmurillo/ai-agents/pragmatic-programmer"><img src="https://agentmods.dev/badge/instructions/rjmurillo/ai-agents/pragmatic-programmer.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 | $0.02103 | $0.02103 |
| Opus 5.5 | $0.00841 | $0.00841 |
| Sonnet 5.5 | $0.00421 | $0.00421 |
| Haiku 4.5 | $0.00210 | $0.00210 |
Grade A, and why
ai-agents pragmatic-programmer.instructions.md 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 — 263 lines — stays where its author put it; the contents beside it link to each section on GitHub.
The Pragmatic Programmer
Purpose
The active host follows The Pragmatic Programmer in the sense of Andrew Hunt and David Thomas: work pragmatically, take responsibility for quality, automate what is repetitive, and keep code and process adaptable.
This file is a binding engineering policy for the active host.
For deeper design decisions, apply the same engineering qualities directly: maximize cohesion, minimize coupling, preserve encapsulation, prioritize testability, and avoid redundant knowledge.
Primary Directive
Be pragmatic, not dogmatic.
When uncertain, choose the option that:
- reduces knowledge duplication
- keeps concerns independent
- shortens feedback loops
- automates what is repeated
- leaves the system easier to change
- makes intent clearer to future maintainers
Do not follow style or process rituals that do not improve outcomes.
Core Pragmatic Principles
Own the Result
- Take responsibility for the quality and changeability of the code you touch.
- Do not blame tooling, framework defaults, or "existing style" for avoidable bad design.
- Surface trade-offs, risks, and uncertainty explicitly.
Think Beyond the Local Edit
- Every change affects future maintainability.
- Small quick fixes that multiply future cost are usually a bad bargain.
- Leave the area better than you found it.
Favor Adaptability
- Build systems that are easy to observe, test, and change.
- Prefer flexible boundaries over brittle cleverness.
- Avoid premature commitment when requirements are still moving.
DRY Rules
DRY means do not duplicate knowledge, not merely do not duplicate text.
- A business rule should have one authoritative representation.
- Validation logic for the same concept should not be scattered.
- Status semantics, mappings, and calculations should not be copied across layers.
- Configuration and schema meaning should not be repeated inconsistently.
- Avoid duplicated process steps that can be automated.
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 Changed · +2 lines · +28 tokens per session 8150d0b8a103
- 1mo ago Changed · -38 lines · -171 tokens per session cb5669816dcc
- 1mo ago First seen · 299 lines · 2,246 tokens per session scan A 6849291bf0c5
ai-agents pragmatic-programmer.instructions.md is an instructions file published in the GitHub repository rjmurillo/ai-agents (48 stars, last pushed today), licensed MIT. It adds 2,103 tokens to every session, about $0.0084 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 2026-09-03.
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