lemma: Instructions file for Codex

AGENTS.md

lemma AGENTS.md is an instructions file for Codex, OpenCode from tkpratardan/lemma. It costs 279 tokens per session, scanned A, a copy of lemma copilot-instructions.md, MIT.

Project instructions for Lemma, a data-analysis environment where answers must be supported by results actually run in the active notebook.

In plain words
What is it for?
Use them for notebook-based data analysis, especially when checking calculations, data sources, joins, measurements, or other evidence before reporting a result.
Why use it?
They reduce mistakes caused by assuming the wrong data structure, units, dates, missing values, joins, or definitions.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md.

This is tkpratardan/lemma's own configuration. It tells Codex and OpenCode how to work on lemma itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything lemma configures →

Reuse

Borrowing it

Nothing to install: this file belongs to tkpratardan/lemma. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/tkpratardan/lemma/master/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/tkpratardan/lemma

Made for: Codex, OpenCode.

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 lemma AGENTS.md

README.md
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Your own site
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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 lemma AGENTS.md

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Per session 279 This file is loaded in full into every session.
When invoked 279 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 100% copy Near-identical to another mod 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 $0.00279 $0.00279
Opus 5.5 $0.00112 $0.00112
Sonnet 5.5 $0.00056 $0.00056
Haiku 4.5 $0.00028 $0.00028

Measured 2mo ago against content hash 72a51a7458ff, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

lemma AGENTS.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 2mo 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.

Origin

This is a copy

100% identical to lemma copilot-instructions.md — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

AGENTS.md · 29 lines

What it actually says

Lemma: smallest defensible answer

Act as a senior data scientist. Answer from executed evidence in the active notebook.

  1. Inspect relevant sources before assuming schema, grain, units, definitions, or dates.
  2. Compute the requested result in the notebook and preserve raw inputs. Shell may locate files; notebook cells perform the analysis.
  3. Check the issue most likely to change the answer, such as the denominator, join cardinality, units, missingness, leakage, split, or identification.
  4. Return the exact requested output with its scope and material uncertainty.

Keep work proportional. Stop when the requested result is supported. Debug freely when execution fails or the evidence exposes ambiguity. Do not add cells only to reprint values already executed.

Notebook actions attach automatically. Use connect only to recover or switch surfaces.

Use one relevant task skill when specialized checks are needed. Do not load a skill for a bounded lookup, join, ranking, count, or aggregate. Use lemma-wrangle only for a real conflict in grain, keys, definitions, units, authority, extraction, or provenance.

Resolve execution errors before presenting a result as validated. Never hand-edit notebook JSON or overwrite raw inputs. A saved artifact supports the answer but does not replace it; a requested list remains a complete list.

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. 2mo ago First seen · 29 lines · 279 tokens per session scan A 72a51a7458ff

Subscribe to this mod's changes

lemma AGENTS.md is an instructions file published in the GitHub repository tkpratardan/lemma (3 stars, last pushed 18d ago), licensed MIT. It adds 279 tokens to every session, about $0.0011 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to lemma copilot-instructions.md, differing in 0 lines, and is treated as a copy.

Related

lemma AGENTS.md compared with instructions from other repositories

lemma AGENTS.md next to 6 instructions from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
lemma AGENTS.mdtkpratardan/lemmaInstructions file318d agoMITA279Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA9,719GitHub Copilot
next.js AGENTS.mdvercel/next.jsInstructions file143ktodayMITA7,461Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchainInstructions file149kyesterdayMITA4,680Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA5,516GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA3,093GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harnessInstructions file274k2d agoMITA4,313Codex, OpenCode