diff --git a/AGENTS.md b/AGENTS.md
index ff09ceb9..ca3cc229 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -1,39 +1,39 @@
 # AGENTS.md
 
 ## Project purpose
 The official Ansible Collection for managing VyOS network appliances (`vyos.vyos` namespace). Provides modules, plugins, action handlers, terminal plugins, and resource modules for BGP, OSPF, firewall, interfaces, NTP, etc.
 
 ## Tech stack
 - Ansible Collection (Galaxy). Python control-plane code under `plugins/`.
 - `galaxy.yml` declares `namespace: vyos`, `name: vyos`, `version: 6.0.0`, dep `ansible.netcommon >= 2.5.1`, license_file `LICENSE` (GPL-3.0).
 - Test stack: `pytest` + `tox-ansible.ini`; lint via flake8, isort, black (line-length 100), pre-commit, ansible-lint.
 - Runtime deps: `paramiko`, `scp` (`requirements.txt`); `bindep.txt` for system deps.
 
 ## Build / test / run
 - Build: `ansible-galaxy collection build` produces a `vyos-vyos-<version>.tar.gz`.
 - Install local dev: `ansible-galaxy collection install . --force`.
-- Test (unit): `source .venv/bin/activate && PYTHONPATH=".collections" python -m pytest tests/unit` (config in `pyproject.toml`). CI (`.github/workflows/tests.yml`) runs the changelog / build-import / ansible-lint / sanity / unit jobs; integration tests live under `tests/integration/` but are not yet wired into CI. Per `README.md`, the collection targets VyOS 1.3.8 / 1.4.1 / 1.5-rolling (no version matrix in the workflow itself).
+- Test (unit): `source .venv/bin/activate && PYTHONPATH=".collections" python -m pytest tests/unit` (config in `pyproject.toml`). CI (`.github/workflows/tests.yml`) runs the changelog / build-import / ansible-lint / sanity / unit-galaxy / unit-source jobs; integration tests live under `tests/integration/` but are not yet wired into CI. Per `README.md`, the collection targets VyOS 1.3.8 / 1.4.1 / 1.5-rolling (no version matrix in the workflow itself).
 
 ## Repository layout
 - `plugins/{action,cliconf,doc_fragments,filter,inventory,module_utils,modules,terminal}/` — collection content.
-- `tests/` — sanity, unit, integration directories. CI (`.github/workflows/tests.yml`) runs sanity + unit only; integration is not yet wired into CI.
+- `tests/` — sanity, unit, integration directories. CI (`.github/workflows/tests.yml`) runs sanity + unit-galaxy + unit-source (plus changelog / build-import / ansible-lint); integration is not yet wired into CI.
 - `docs/` — generated module docs.
 - `meta/`, `changelogs/`, `CHANGELOG.rst` — Galaxy + release metadata.
 - `pyproject.toml` (black/pytest config), `.flake8`, `.isort.cfg`, `.ansible-lint`, `.pre-commit-config.yaml`.
 - `.github/workflows/` — `tests.yml`, `release.yml`, `codecoverage.yml`, `cla-check.yml`, `ah_token_refresh.yml`, `check_label.yaml`.
 
 ## Cross-repo context
 - Consumed by Ansible users running playbooks against VyOS routers built by `vyos/vyos-build`.
 - The `vyos.vyos` collection talks to VyOS via `network_cli` connections; supports the same train branches (`current`, `circinus`, `sagitta`, `equuleus`).
 
 ## Conventions
 - Commit / PR title: `T12345: description` (Phorge ID at https://vyos.dev mandatory).
 - Every PR must include exactly one changelog fragment under `changelogs/fragments/`; use `doc_changes` for documentation-only updates, or `trivial` for tooling / housekeeping changes.
 - Default branch `main` (not `current` — this repo predates the rename convention).
 - Issues tracked at https://vyos.dev (see `galaxy.yml`).
 - Codecov + CodeRabbit configured (`codecov.yml`, `.coderabbit.yaml`).
 
 ## Notes for future contributors
 - Galaxy versioning is independent of VyOS train versioning — bump in `galaxy.yml` per release.
 - Tested matrix is in README; expand only after smoketesting against real images.
 - `PR408_README.md` plus `pr408-diagram.png` document a non-trivial historical refactor; read before touching resource-module structure.
diff --git a/changelogs/fragments/T8595_add_agents_md.yml b/changelogs/fragments/T8595_add_agents_md.yml
new file mode 100644
index 00000000..5d7fb0a4
--- /dev/null
+++ b/changelogs/fragments/T8595_add_agents_md.yml
@@ -0,0 +1,2 @@
+trivial:
+  - Add AGENTS.md tool-neutral contributor documentation, with .github/copilot-instructions.md symlink for Copilot code review compatibility.