Software developers
The daily loop with coding agents: plan first, make tests the contract, keep diffs small, run tasks in parallel worktrees, get an agent review, and let hooks and routines handle formatting, safety and chores.
For Software engineers who write, review and ship code every day
Ship small, tested changes while the agent types and you decide what merges
- A plan, test, implement, verify loop that turns a ticket into a reviewable pull request
- Tests written first, so the agent cannot call a change done until they pass
- Two or three tasks running at once in separate worktrees, each with its own small pull request
- An agent review on every branch before a teammate spends time on it
- Dependency bumps and flaky-test reports drafted overnight for you to review
On this page
- Where AI helps in this job
- Start in 15 minutes
- The tools developers use
- Members only: Workflow: from ticket to pull request
- Members only: Workflow: parallel tasks in worktrees
- Members only: Workflow: an agent review before a human sees it
- Members only: Workflow: tickets and docs over MCP
- Members only: A skill for developers
- Members only: Guardrails and hooks
- Members only: Routines that run without you
- Members only: Prompt ladder for developers
- Members only: Measure it
- Members only: Risks and what not to automate
A coding agent reads your repository, runs your tests and edits files. That moves your job from typing to deciding: what to build, what correct means, and whether a diff is safe to merge. This page gives you the loop, the prompts and the guardrails for that job in Claude Code, with the Codex, Cursor, Copilot and Gemini CLI equivalents where they exist.
Where AI helps in this job#
| Task | What AI does well | What you still own |
|---|---|---|
| Reading unfamiliar code | Traces a request through files and explains each step with file and line references | Checking the explanation against what the code does at runtime |
| Planning a change | Lists the files to touch, the order, edge cases and open questions | The approach, the scope and what you will not do |
| Writing tests first | Turns acceptance criteria into failing tests in your framework's style | What correct means, and tests that assert behavior instead of implementation |
| Implementing | Writes the smallest change that makes the tests pass, following nearby patterns | Design, naming, and a diff small enough to review |
| Debugging | Reproduces from a stack trace, adds logging, bisects, proposes a root cause | Confirming the root cause instead of accepting a symptom patch |
| Review | A first pass for logic errors, missing tests and security smells | The approval, and anything about product or architecture |
| Refactors and migrations | Mechanical edits across dozens of files, in parallel | Sequencing, rollout and backwards compatibility |
| Dependency updates | Reads changelogs, bumps versions, fixes broken calls, runs the suite | Merging, and the risk call on major versions |
| Pull request descriptions | Summarizes the diff and pastes the test evidence | Accuracy, and what the reviewer needs to know |
Agents are weakest where they cannot check their own work. Without a test, a build or a type check to run, a change is a confident guess and you become the test suite. They also invent APIs and flags from older library versions, drift on large vague tasks, and do worse on performance, concurrency and security-sensitive code than on routine code. Keep tasks small, give every task a check, and read every diff.
Start in 15 minutes#
These three prompts work in any agent with access to your repository (Claude Code, Codex, Cursor, Copilot agent mode, Gemini CLI) and as pasted text in a chat app.
Prompt
Explain a code path before you touch it
Read [FILE OR FOLDER]. Explain what happens from [ENTRY POINT, FOR EXAMPLE POST /orders] to [OUTCOME, FOR EXAMPLE A NEW ROW IN THE orders TABLE]. List each function in order with its file and line, what it reads and writes, and where it can fail. Do not change any files.
Good output is a numbered call chain with file and line references and the failure points marked. Open two or three of the cited lines and confirm they say what the agent claims.
Prompt
Plan before code
I need to [CHANGE, FOR EXAMPLE ADD A RETRY TO THE PAYMENT WEBHOOK HANDLER]. Do not write code yet. Propose a plan: 1. The files you will change and why. 2. The tests you will add first, with their names and what each one asserts. 3. Edge cases and failure modes. 4. Anything you are unsure about, as questions for me. Keep the change under [200] lines if you can. Wait for my approval before you edit anything.
Good output names real files and real test cases and asks at least one question. If the plan touches files you did not expect, ask why before you approve it.
Prompt
Tests as the contract
Write failing tests for this behavior: [ACCEPTANCE CRITERIA]. Use the test framework and style already in [TEST FOLDER]. Run the tests and show me the output that proves they fail for the right reason: an assertion about the missing behavior, not an import error or a typo. Do not write the implementation yet.
Good output is red tests whose failure messages describe the missing behavior. Run them once yourself. A test that fails for the wrong reason will pass for the wrong reason too.
The tools developers use#
- Claude Code runs in the terminal, IDEs, the desktop app and the browser. It has plan mode, skills, hooks, subagents,
claude --worktreefor parallel sessions, routines for scheduled work, and/code-reviewand/security-review. It readsCLAUDE.md, and readsAGENTS.mdwhen a repository has noCLAUDE.md. - OpenAI Codex runs as a CLI, an IDE extension, cloud tasks and inside the ChatGPT desktop app. It reads
AGENTS.md, loads skills from.agents/skills, runs hooks from.codex/hooks.json, has/planand/review, and reviews pull requests when you comment@codex review. - Cursor is an editor built around an agent: Plan Mode (Shift+Tab), rules in
.cursor/rulesorAGENTS.md, hooks in.cursor/hooks.json, parallel agents in worktrees, Cloud Agents, and Bugbot for pull request review. - GitHub Copilot has agent mode in VS Code and JetBrains, Copilot CLI, the Copilot cloud agent (assign it an issue and it opens a pull request) and Copilot code review. It reads
AGENTS.md,.github/copilot-instructions.mdand skills in.github/skills. - Gemini CLI is Google's open source terminal agent, with plan mode, skills, hooks and MCP. It reads
GEMINI.md; addAGENTS.mdto itscontext.fileNamesetting to share one file.
Write conventions once: put them in AGENTS.md, and put skills in .agents/skills/, which Codex, Cursor, Copilot and Gemini CLI read. Claude Code reads .claude/skills/, so symlink each skill folder there.
Workflow: from ticket to pull request
Members only below this line
Get the full Software developers playbook free
What you get on this page:
- 4 step-by-step workflows
- 14 prompts
- 1 skill
- 2 hooks
- 2 routines
Also in the members part
- Workflow: parallel tasks in worktrees
- Workflow: an agent review before a human sees it
- Workflow: tickets and docs over MCP
- A skill for developers
- Guardrails and hooks
- Routines that run without you
- Prompt ladder for developers
- Measure it
- Risks and what not to automate
Sources
Checked against these on 13 Oct 2026.
- Best practices for Claude Code (opens in a new tab)code.claude.com
- Claude Code hooks reference (opens in a new tab)code.claude.com
- Automate actions with hooks (Claude Code) (opens in a new tab)code.claude.com
- Extend Claude with skills (opens in a new tab)code.claude.com
- Run parallel sessions with worktrees (opens in a new tab)code.claude.com
- Code Review (Claude Code) (opens in a new tab)code.claude.com
- Automate work with routines (opens in a new tab)code.claude.com
- Claude Code GitHub Actions (opens in a new tab)code.claude.com
- Connect Claude Code to tools via MCP (opens in a new tab)code.claude.com
- Codex: custom instructions with AGENTS.md (opens in a new tab)learn.chatgpt.com
- Codex: build skills (opens in a new tab)learn.chatgpt.com
- Codex code review in GitHub (opens in a new tab)learn.chatgpt.com
- Cursor hooks (opens in a new tab)cursor.com
- Cursor third-party hooks (Claude Code compatibility) (opens in a new tab)cursor.com
- Cursor Bugbot (opens in a new tab)cursor.com
- About agent skills (GitHub Copilot) (opens in a new tab)docs.github.com
- Using GitHub Copilot code review (opens in a new tab)docs.github.com
- Gemini CLI skills (opens in a new tab)geminicli.com
- Linear MCP server (opens in a new tab)linear.app
- Atlassian MCP server: getting started (opens in a new tab)support.atlassian.com
- METR: measuring the impact of early-2025 AI on experienced open-source developer productivity (opens in a new tab)metr.org
- METR: uplift study update (February 2026) (opens in a new tab)metr.org