| --- |
| pretty_name: AGENTS.md and CLAUDE.md in popular GitHub repositories (snapshot 2026-10-16) |
| license: other |
| license_name: per-repository |
| license_details: File texts keep the license of the repository they come from (column `license`). See the Licensing section. |
| language: |
| - en |
| size_categories: |
| - 10K<n<100K |
| tags: |
| - agents-md |
| - claude-md |
| - coding-agents |
| - agent-instructions |
| - github |
| - software-engineering |
| configs: |
| - config_name: files |
| data_files: files.parquet |
| default: true |
| - config_name: repos |
| data_files: repos.parquet |
| - config_name: population |
| data_files: population.parquet |
| --- |
| |
| # AGENTS.md and CLAUDE.md in popular GitHub repositories |
|
|
| A census of the agent context files `/AGENTS.md` and `/CLAUDE.md` in **22,854** popular, active |
| open-source GitHub repositories. The snapshot was taken on **2026-10-16**. This is the core data of the study |
| *github-coding-metastudy* by Pawel Zarzycki: an arXiv paper and an interactive companion website. |
|
|
| **Every repository in the population was checked; this is a census, not a sample.** |
| 6,006 repositories (26.3%) have at least one of the two files: |
| 2,566 have AGENTS.md only, 1,052 have CLAUDE.md only, and 2,388 have both. |
|
|
| ## Paper |
|
|
| This dataset accompanies |
| [What Open-Source Projects Tell Their Coding Agents: A Census of AGENTS.md and CLAUDE.md](https://arxiv.org/abs/2610.31715). |
|
|
| ## Population |
|
|
| At the snapshot date, a repository is in the population if all of the following hold: |
|
|
| - it is public on github.com; |
| - its primary language (GitHub Linguist) is one of Python, JavaScript, TypeScript, Java, C#, C++, C, Go, Rust, |
| PHP, Ruby, Kotlin or Swift; |
| - it has at least 1,000 stars; |
| - it was pushed within 90 days (`pushed_at` >= 2026-07-18, a push to any branch counts); |
| - it is neither a fork nor archived. |
|
|
| ## Files |
|
|
| The study covers only `/AGENTS.md` and `/CLAUDE.md`, at the repository root, with exact case, on the |
| default branch, in their current version (the commit is in `head_oid`). Other formats are out of scope, for |
| example `.cursor/rules`, `.github/copilot-instructions.md` and nested AGENTS.md files. |
|
|
| ## Configs |
|
|
| All three configs join on `full_name` (`owner/repo`). |
|
|
| ### `files` (8,394 rows): one row per file |
|
|
| | column | meaning | |
| |---|---| |
| | `full_name`, `path` | repository and file (`AGENTS.md` or `CLAUDE.md`) | |
| | `license` | the repository's license, an SPDX id from GitHub; `NOASSERTION` means GitHub couldn't identify it, null means no license file | |
| | `head_oid`, `head_date` | the default-branch commit the file was read from, and its date | |
| | `is_symlink`, `link_target` | whether the file is a symlink, and its target path | |
| | `byte_size` | size in bytes as reported by GitHub | |
| | `text_status` | `included`, `withheld_license`, `unresolved_symlink` or `binary` | |
| | `text` | the file content (UTF-8); null unless `text_status = included` | |
|
|
| Symlinks are resolved, so a symlink row carries the **target's** text. Of the 874 symlink rows, |
| most are a CLAUDE.md that points to the same repository's AGENTS.md. Filter on `is_symlink` to avoid |
| counting that content twice. |
|
|
| Text status in this release: |
|
|
| | text_status | count | |
| |---|---:| |
| | included | 8,387 | |
| | unresolved_symlink | 6 | |
| | binary | 1 | |
|
|
| Included texts: 79.0 MB. |
|
|
| ### `repos` (6,006 rows): one row per repository with at least one file |
|
|
| Repository metadata from GitHub at enrich time: |
| - `stars`, `forks`, `watchers`, `disk_usage_kb`, `code_bytes`; |
| - `languages` (bytes per language), `topics`, `license`, `description`, `homepage_url`, `default_branch`, |
| `created_at`, `pushed_at`, `is_fork`, `is_archived`, `is_template`; |
| - `releases`, `open_issues`, `closed_issues`, `open_prs`, `merged_prs`, `commits_total`. |
|
|
| Activity metrics: |
| - `commits_12m`: default-branch commits in the 365 days before the snapshot; |
| - `recent_*`: computed from the latest (up to) 100 of those commits. They are `recent_sample` (how many |
| commits were sampled), `recent_authors`, `recent_human_authors` (bots excluded), |
| `recent_bot_commits` and `recent_ai_commits` (commits with a co-author trailer or signature of |
| Claude, Codex, Copilot, Cursor, Devin, Aider or Gemini). |
|
|
| How the two files relate: |
| - `relation`: one label per repository. The rules are applied in order and the first match wins: |
| symlink, thin `@AGENTS.md` import (300 characters or fewer), short pointer, import plus own content, |
| identical copies, separate files; |
| - `relation_detail`: for example, the symlink target. |
|
|
| | relation | count | |
| |---|---:| |
| | AGENTS.md only | 2,549 | |
| | CLAUDE.md only | 1,040 | |
| | both: CLAUDE.md is a thin @AGENTS.md import (<=300 chars) | 771 | |
| | both: CLAUDE.md is a symlink to AGENTS.md | 629 | |
| | both: separate files | 262 | |
| | both: separate files, CLAUDE.md mentions AGENTS.md | 171 | |
| | both: AGENTS.md is a symlink to CLAUDE.md | 155 | |
| | both: CLAUDE.md is a short pointer to AGENTS.md | 140 | |
| | both: CLAUDE.md imports @AGENTS.md and adds content | 101 | |
| | both: separate files, AGENTS.md mentions CLAUDE.md | 64 | |
| | both: identical copies | 40 | |
| | both: symlinks to the same other file | 28 | |
| | both: AGENTS.md only imports or points to CLAUDE.md | 27 | |
| | AGENTS.md only (symlink to another file) | 17 | |
| | CLAUDE.md only (symlink to another file) | 12 | |
|
|
| ### `population` (22,854 rows): every repository that was checked |
|
|
| | column | meaning | |
| |---|---| |
| | `full_name`, `repo_id` | repository | |
| | `primary_language`, `stars`, `created_at`, `pushed_at` | from GitHub search at discovery time | |
| | `found` | the repository still resolved when presence was checked | |
| | `has_agents_md`, `has_claude_md` | whether each root file exists | |
| | `agents_md_size`, `claude_md_size` | file size in bytes, if the file exists | |
|
|
| Use `population` for adoption rates, for example by language or star band. Note that `population.stars` and |
| `population.pushed_at` come from search time, while the `repos` columns come from enrich time a few hours |
| later, so the values can differ slightly. |
|
|
| ## Collection |
|
|
| All data came through the GitHub GraphQL and REST APIs with one token, on 2026-10-16; no repository was |
| cloned. The pipeline's code and its parameters are in the study repository (`metastudy/`). |
|
|
| Known limitations: |
| - 103 adopters have a default-branch HEAD older than the 90-day window. They passed the filter because of |
| pushes to other branches. |
| - Stars and `pushed_at` are a snapshot, so repositories near the 1,000-star cut-off move in and out over time. |
| - A repository is classified only by its primary language. |
| - 7 files have no text: 6 symlinks can't be resolved (their targets are outside the repository or not |
| in it), and GitHub flags 1 file as binary. |
|
|
| ## Licensing |
|
|
| The file texts are third-party content. Each text keeps the license of the repository it comes from, |
| given in `license`. Check that license, and attribute the repository (`full_name`, `head_oid`), before |
| you reuse a text. |
|
|
| This release includes every text that was collected. 1,358 included texts come from repositories with `NOASSERTION` or no license; their reuse terms are unclear. |
|
|
| Repository licenses among adopters: |
|
|
| | license | count | |
| |---|---:| |
| | MIT | 2,334 | |
| | Apache-2.0 | 1,525 | |
| | NOASSERTION | 816 | |
| | GPL-3.0 | 389 | |
| | AGPL-3.0 | 347 | |
| | (none) | 157 | |
| | BSD-3-Clause | 131 | |
| | GPL-2.0 | 98 | |
| | MPL-2.0 | 50 | |
| | BSD-2-Clause | 38 | |
| | LGPL-3.0 | 31 | |
| | CC0-1.0 | 12 | |
| | ISC | 11 | |
| | LGPL-2.1 | 8 | |
| | Unlicense | 8 | |
| | CC-BY-SA-4.0 | 7 | |
| | EPL-2.0 | 7 | |
| | CC-BY-4.0 | 6 | |
| | Zlib | 6 | |
| | EUPL-1.2 | 5 | |
| | MIT-0 | 4 | |
| | OSL-3.0 | 3 | |
| | 0BSD | 3 | |
| | BSL-1.0 | 2 | |
| | EPL-1.0 | 2 | |
| | MS-PL | 1 | |
| | WTFPL | 1 | |
| | OFL-1.1 | 1 | |
| | UPL-1.0 | 1 | |
| | ECL-2.0 | 1 | |
| | PostgreSQL | 1 | |
|
|
| The metadata columns (counts, flags, labels) are facts about public repositories, compiled by the author. |
|
|
| ## Personal information |
|
|
| The texts are published files from public repositories. Some contain names, GitHub handles or e-mail |
| addresses of maintainers: 302 of the included texts contain at least one e-mail address. They were |
| not removed. Please don't use this dataset to contact or profile individuals. |
|
|
| ## Citation |
|
|
| If you use this dataset in your research, please cite: |
|
|
| ```bibtex |
| @misc{zarzycki2026codingagents, |
| title = {What Open-Source Projects Tell Their Coding Agents: |
| A Census of {AGENTS.md} and {CLAUDE.md}}, |
| author = {Pawel Zarzycki}, |
| year = {2026}, |
| eprint = {2610.31715}, |
| archivePrefix = {arXiv}, |
| primaryClass = {cs.SE}, |
| url = {https://arxiv.org/abs/2610.31715} |
| } |
| ``` |
|
|
|
|
