docs(agents): add a GEMINI.md pointer to the maintained instructions

[hyperpolymath]

Adds a GEMINI.md pointer file to this repository.

Why. An estate-wide census found a large asymmetry in agent-instruction
files: CLAUDE.md was present almost everywhere, GEMINI.md in a handful of
repositories. Any coding agent that looks for GEMINI.md and does not find one
proceeds with no repository-specific instructions at all.

This file is a pointer, not a second copy of the instructions. Duplicating
guidance across per-agent files guarantees the copies drift. The pointer
redirects to whichever file this repository actually maintains — AGENTS.md
where one exists, otherwise CLAUDE.md — and says to retarget it at
AGENTS.md when one lands.

How this commit was built. The change was made with git plumbing against
origin/<default branch>, not by staging a working tree. The branch contains
exactly one commit adding exactly one file, and carries none of the unrelated
local state present in this checkout. A per-repository assertion required
git diff --name-only <base> <commit> to equal the expected path set exactly,
or the branch was never created.

This PR is opened as a draft on purpose. It is part of a bulk campaign and
is not requesting a merge. Review and merge at your discretion.

🤖 Generated with Claude Code

https://claude.ai/code/session_011eQ7hibx92N7fBDtwgReWk

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Advanced

Run ID: b6e3ee6e-a56b-4b68-a28f-63bc251bcff4

📥 Commits

Reviewing files that changed from the base of the PR and between 556d646 and 134f2f4.

📒 Files selected for processing (1)

• GEMINI.md

Included review availability: Your plan provides up to 1 included review per hour; 0 remain after this review.

📜 Recent review details

⏰ Context from checks skipped due to timeout. (12)

• GitHub Check: governance / Validate Hypatia Baseline
• GitHub Check: rust-ci / llvm-cov line coverage
• GitHub Check: rust-ci / Cargo audit (security)
• GitHub Check: rust-ci / Cargo check + clippy + fmt
• GitHub Check: T1 / eprover
• GitHub Check: T1 / minizinc
• GitHub Check: Validate A2ML manifests
• GitHub Check: T1 / chuffed
• GitHub Check: T1 / cvc5
• GitHub Check: Validate eclexiaiser manifest
• GitHub Check: Empty-linter (invisible characters)
• GitHub Check: PR (address)

⚠️ CI failures not shown inline (6)

GitHub Actions: MVP Smoke (Best Effort) / 0_MVP Smoke.txt: docs(agents): add a GEMINI.md pointer to the maintained instructions

Conclusion: failure

View job details

##[group]GITHUB_TOKEN Permissions
 Contents: read
 Metadata: read
 ##[endgroup]
 Secret source: Actions
 Using locked action versions from the workflow's lockfile
 Prepare workflow directory
 Prepare all required actions
 Getting action download info
 ##[error]lockfile verification did not produce a result for this action. Lockfile pin 4360b52568e2003a75bf9bc1d59f33a8e3fc893c for `dtolnay/rust-toolchain` does not match ref `stable`. Ensure the pinned commit exists on the expected branch or tag. lockfile verification did not produce a result for this action

---

GitHub Actions: Cargo Audit / 0_Dependency audit.txt: docs(agents): add a GEMINI.md pointer to the maintained instructions

Conclusion: failure

View job details

##[group]GITHUB_TOKEN Permissions
 Contents: read
 Metadata: read
 ##[endgroup]
 Secret source: Actions
 Using locked action versions from the workflow's lockfile
 Prepare workflow directory
 Prepare all required actions
 Getting action download info
 ##[error]Lockfile pin 4360b52568e2003a75bf9bc1d59f33a8e3fc893c for `dtolnay/rust-toolchain` does not match ref `stable`. Ensure the pinned commit exists on the expected branch or tag

---

GitHub Actions: Server Boot Gate / 0_Boot Gate.txt: docs(agents): add a GEMINI.md pointer to the maintained instructions

Conclusion: failure

View job details

##[group]GITHUB_TOKEN Permissions
 Contents: read
 Metadata: read
 ##[endgroup]
 Secret source: Actions
 Using locked action versions from the workflow's lockfile
 Prepare workflow directory
 Prepare all required actions
 Getting action download info
 ##[error]lockfile verification did not produce a result for this action. Lockfile pin 4360b52568e2003a75bf9bc1d59f33a8e3fc893c for `dtolnay/rust-toolchain` does not match ref `stable`. Ensure the pinned commit exists on the expected branch or tag

---

GitHub Actions: MVP Smoke (Best Effort) / MVP Smoke: docs(agents): add a GEMINI.md pointer to the maintained instructions

Conclusion: failure

View job details

##[group]GITHUB_TOKEN Permissions
 Contents: read
 Metadata: read
 ##[endgroup]
 Secret source: Actions
 Using locked action versions from the workflow's lockfile
 Prepare workflow directory
 Prepare all required actions
 Getting action download info
 ##[error]lockfile verification did not produce a result for this action. Lockfile pin 4360b52568e2003a75bf9bc1d59f33a8e3fc893c for `dtolnay/rust-toolchain` does not match ref `stable`. Ensure the pinned commit exists on the expected branch or tag. lockfile verification did not produce a result for this action

---

GitHub Actions: Cargo Audit / Dependency audit: docs(agents): add a GEMINI.md pointer to the maintained instructions

Conclusion: failure

View job details

##[group]GITHUB_TOKEN Permissions
 Contents: read
 Metadata: read
 ##[endgroup]
 Secret source: Actions
 Using locked action versions from the workflow's lockfile
 Prepare workflow directory
 Prepare all required actions
 Getting action download info
 ##[error]Lockfile pin 4360b52568e2003a75bf9bc1d59f33a8e3fc893c for `dtolnay/rust-toolchain` does not match ref `stable`. Ensure the pinned commit exists on the expected branch or tag

---

GitHub Actions: Server Boot Gate / Boot Gate: docs(agents): add a GEMINI.md pointer to the maintained instructions

Conclusion: failure

View job details

##[group]GITHUB_TOKEN Permissions
 Contents: read
 Metadata: read
 ##[endgroup]
 Secret source: Actions
 Using locked action versions from the workflow's lockfile
 Prepare workflow directory
 Prepare all required actions
 Getting action download info
 ##[error]lockfile verification did not produce a result for this action. Lockfile pin 4360b52568e2003a75bf9bc1d59f33a8e3fc893c for `dtolnay/rust-toolchain` does not match ref `stable`. Ensure the pinned commit exists on the expected branch or tag

🧰 Additional context used

🧠 Learnings (1)

📓 Common learnings

Learnt from: CR
Repo: hyperpolymath/echidna

Timestamp: 2026-09-08T23:50:58.470Z
Learning: Do not duplicate rules here.

🪛 GitHub Check: Hypatia

GEMINI.md

[warning] 1-1: Hypatia root_hygiene: stale
Stale AI session file -- delete

🔇 Additional comments (1)

GEMINI.md (1)

1-8: LGTM!

---

📝 Summary

Summary by CodeRabbit

• Documentation
  • Added guidance for coding agents to consult the existing project instructions.
  • Documented the intended future transition to a dedicated agent guidance file.

Walkthrough

GEMINI.md now directs coding agents to read CLAUDE.md, excludes Claude Code-specific instructions, and states that the pointer will later target AGENTS.md.

Changes

Agent guidance

Layer / File(s)	Summary
Add agent guidance pointer GEMINI.md	Adds guidance for coding agents, excludes Claude Code-specific instructions, and defines the future AGENTS.md target.

Priority: ⬇️ Low

Estimated code review effort: 1 (Trivial) | ~2 minutes

Merge Risk: ⚪ Minimal · up to 134f2

This adds a GEMINI.md pointer to the existing repository guidance without changing application behavior, data handling, or deployment behavior. No current merge-blocking risk remains.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly and concisely describes the addition of a GEMINI.md pointer to the maintained agent instructions.
Description check	✅ Passed	The description explains the GEMINI.md pointer, its purpose, its target instructions, and the draft status. It relates directly to the changeset.

✨ Finishing Touches 💡 1

🛠️ Fix failing CI checks 💡

• Create stacked PR
• Commit on current branch

---

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