no-synthetic-data

no-synthetic-data is a cursor rule for Cursor from sweeden-ttu/canvas-lms-mcp. It costs 824 tokens per session, scanned A, original, MIT.

A project-wide rule that forbids synthetic, mock, and dummy data in code, tests, examples, and documentation. It requires claims to be checked with a hypothesis, a real experiment, and evidence, followed by review.

In plain words
What is it for?
Use it to guide test design, examples, evidence reviews, and experiments where real sources or observed behavior should replace fabricated data.
Why use it?
It prevents demonstrations and tests from appearing to work only because they use invented or unrealistic data.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/.

Good fit Use it to guide test design, examples, evidence reviews, and experiments where real sources or observed behavior should replace fabricated data.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/sweeden-ttu/canvas-lms-mcp/no-synthetic-data
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.

Clone the repo
git clone --depth 1 https://github.com/sweeden-ttu/canvas-lms-mcp

Made for: Cursor.

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 no-synthetic-data

README.md
[![agentmods](https://agentmods.dev/badge/rules/sweeden-ttu/canvas-lms-mcp/no-synthetic-data/github.svg)](https://agentmods.dev/rules/sweeden-ttu/canvas-lms-mcp/no-synthetic-data)
Your own site
<a href="https://agentmods.dev/rules/sweeden-ttu/canvas-lms-mcp/no-synthetic-data"><img src="https://agentmods.dev/badge/rules/sweeden-ttu/canvas-lms-mcp/no-synthetic-data/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 no-synthetic-data

Your own site · 80×15
<a href="https://agentmods.dev/rules/sweeden-ttu/canvas-lms-mcp/no-synthetic-data"><img src="https://agentmods.dev/badge/rules/sweeden-ttu/canvas-lms-mcp/no-synthetic-data.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 824 This file is loaded in full into every session.
When invoked 824 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00824 $0.00824
Opus 5 $0.00412 $0.00412
Sonnet 5 $0.00165 $0.00165
Haiku 4.5 $0.00082 $0.00082

Measured 11d ago against content hash d730728daeb9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

no-synthetic-data 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 11d 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.

.cursor/rules/no-synthetic-data.mdc · 54 lines

How it starts

The opening of the file, as written. The whole thing — 54 lines — stays where its author put it; the contents beside it link to each section on GitHub.

No Synthetic, Mock, or Dummy Data (Global Rule)

Scope

This rule applies to all work in this project: evidence evaluators, examples, templates, presentations, tests, documentation, and any code or content that could introduce fake data.

Prohibited

  • Synthetic data: Artificially generated data that is not from a real source (e.g. fabricated API responses, generated user records).
  • Mock data: Placeholder or fake data used to simulate behavior (e.g. mock objects returning hardcoded values, mock APIs with fake JSON).
  • Dummy data: Filler data (e.g. "foo", "[email protected]", "Sample User") used in examples, templates, or presentations instead of real or experiment-derived data.

Do not use synthetic, mock, or dummy data in evidence evaluators, examples, templates, presentations, or tests. If you find such data, do not leave it in place; replace it using the process below.

Required alternative: Hypothesis, experiment, evidence

Whenever fake data would be introduced:

  1. Hypothesis: State a testable hypothesis for what real data or behavior is needed (e.g. "Canvas API returns assignments in this shape").
  2. Planned experiment: Define a concrete experiment to obtain or validate real data (e.g. call the live Canvas API, fetch real course content, crawl real documentation).
  3. Evaluate evidence and results: Run the experiment, collect evidence, and update beliefs (e.g. via BayesianOrchestrator or EvidenceEvaluatorAgent). Use the resulting real data in examples, templates, and presentations.

Prefer live/verified endpoints, real course IDs from test_hints.json, and real documentation URLs. If real data cannot be obtained (e.g. no API key), document the gap and the minimal experiment that would be run; do not substitute mock/synthetic/dummy data.

Required: review-changes step

Every change set (PR, commit batch, or delivered task) must include a review-changes step that:

  1. Evaluates step-by-step instructions: Review the instructions that were followed and confirm they do not rely on synthetic/mock/dummy data.
  2. Performs peer review: Apply a peer review (e.g. via the cs-peer-reviewer-trustworthy-ai skill or equivalent) to the changes.
  3. Attempts reproduction: Run the same steps in a clean environment and verify outcomes (e.g. re-run tests, re-fetch data, re-build presentation).
  4. Accept or reject premise:
    • Accept: If reproduction succeeds and no synthetic/mock/dummy data was introduced, accept the premise and keep the change.
    • Reject: If mock/synthetic/dummy data would have been used or results cannot be reproduced, reject the premise and revert or rewrite the change so that real data and reproducible evidence are used instead.

Read the full file on GitHub · 54 lines

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. 11d ago First seen · 54 lines · 824 tokens per session scan A d730728daeb9

Subscribe to this mod's changes

no-synthetic-data is a cursor rule published in the GitHub repository sweeden-ttu/canvas-lms-mcp (0 stars, last pushed 6mo ago), licensed MIT. It adds 824 tokens to every session, about $0.0041 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.