What is non_deterministic_sw_eng api.instructions.md?

A set of project instructions for building authenticated APIs. It covers request checks, response shapes, authentication, and expected errors.

Adding or changing API routes with Zod validation, standard response formats, route authentication, and application-level error handling.

It gives developers consistent rules for validating requests and returning success or error responses. This reduces differences between API endpoints and makes failures easier to handle.

non_deterministic_sw_eng api.instructions.md — Instructions file by popoloni

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.

agentmods

npx agentmods add instructions/popoloni/non_deterministic_sw_eng/api

Clone the repo

git clone --depth 1 https://github.com/popoloni/non_deterministic_sw_eng

Made for: GitHub Copilot.

Per session 184 This file is loaded in full into every session.

When invoked 184 The same file — it is already loaded in full.

Security scan A 0 findings. Scan, not verified.

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.

Model	Per session	Once invoked
Fable 5	$0.00184	$0.00184
Opus 5	$0.00092	$0.00092
Sonnet 5	$0.00037	$0.00037
Haiku 4.5	$0.00018	$0.00018

Measured 2d ago against content hash eb299d655376, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

non_deterministic_sw_eng api.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 2d 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.

04-context-engineering/copilot-instructions/.github/instructions/api.instructions.md · 35 lines

What it actually says

API Development Guidelines

When working with API endpoints in this project:

Validation

Use zod schemas for all request validation
Validate at the route level, not in business logic
Return 400 for validation errors with details

Response Format

// Success response
{ data: T, meta?: { page, total } }

// Error response  
{ error: { code: string, message: string, details?: unknown } }

Authentication

All routes require auth by default
Use @public decorator for public routes
Access user via req.user after auth middleware

Error Handling

Use ApplicationError for expected errors
Let unexpected errors bubble to global handler
Log errors with request context

Reference

See src/api/users/ for canonical implementation.

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.

2d ago First seen · 35 lines · 184 tokens per session scan A eb299d655376

Subscribe to this mod's changes

non_deterministic_sw_eng api.instructions.md is an instructions file published in the GitHub repository popoloni/non_deterministic_sw_eng (6 stars, last pushed 8mo ago), licensed MIT. It adds 184 tokens to every session, about $0.0009 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 2026-08-31.

Backend and APIs

spec-kit AGENTS.md

AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.

github/spec-kit · 7,104 tokens

vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

microsoft/vscode · 6,785 tokens

non_deterministic_sw_eng api.instructions.md