# Use Copilot > Use when delegating bounded coding, audit, or review work to GitHub Copilot CLI. Copilot's edge is GitHub-native MCP integration (issues, PRs, code search) on a GitHub Copilot subscription with no separate billing. Sibling skill of use-codex / use-gemini / use-cursor / use-droid. - Skill: `oimiragieo/use-copilot` (Agent Skill) - Install (CLI): `npx skillmds@latest add oimiragieo/use-copilot` - Raw SKILL.md: https://api.skillmd.com/api/skills/oimiragieo/use-copilot/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: oimiragieo (https://skillmd.com/u/oimiragieo) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/oimiragieo/use-copilot --- # Use Copilot ## Core rule **Copilot is a bounded implementation worker that shines for GitHub-integrated work. Claude owns the plan, the prompt file, the audit synthesis, the tests, the commits, and the final answer to the user.** Copilot's killer features over other CLIs: 1. **GitHub MCP built-in** — `--add-github-mcp-toolset all` exposes issues, PRs, releases, code search to the agent. Saves you wiring an MCP server yourself when the task involves "look at PR #123 and..." 2. **Copilot subscription** — if you already pay for Copilot Pro/Business, the CLI usage is included; no separate API token to manage. 3. **Reasoning effort knob** — `--effort xhigh` for deep audits, `--effort low` for cheap fan-out. ## When to use vs when to skip | Use copilot | Use Claude Agent / other CLI | |---|---| | Tasks that require reading GitHub issues / PRs / code-search results | Local-only tasks (codex/cursor are simpler) | | GitHub Actions debugging using actual run logs | Pure-Python audit (use codex) | | Cross-repo work where the agent must navigate org repos | Single-repo bounded edits (use cursor) | | When the user already pays for Copilot and wants to amortize the sub | When other CLIs already match — don't add a 5th workflow | | Audit pass with `--effort xhigh` for second opinion | Real-time iteration (Edit tool is faster) | **Don't use copilot for:** - Tasks that don't touch GitHub — codex / gemini / cursor are typically faster setups - Workflows that need raw API access to non-GitHub services (no inherent advantage over codex) - Live debugging needing mid-flight Claude context ## Available models (Copilot picker — verified 2026-07-01) Use `--model ` to switch; **`Auto` is the default and gets a 10% quota discount** (leave `--model` off to use it). The **Quota** column is Copilot's premium-request multiplier (higher = more of your monthly quota burned per request) — it's the load-bearing cost signal on Copilot, so pick the cheapest model that clears the task. Confirm exact `--model` slugs with `copilot --model -p ping` (display names below; slug format is lowercased-dotted, e.g. `claude-opus-4.8`, `gemini-3.1-pro`). | Model ID | Family | Quota | Best for | Headline benchmark | Don't use for | |---|---|---|---|---|---| | `gpt-5.5` | OpenAI | **57x** | **Frontier review** (auth/billing/migrations), terminal/agentic work | Terminal-Bench 2.0 **82.7% (SOTA)**, GDPval 84.9% | Routine work — priciest seat by far | | `gpt-5.4` | OpenAI | 6x | Default everyday coding, multi-file edits | SWE-Bench Pro 57.7%, OSWorld 75.0% | Beyond 272K context (price cliff) | | `gpt-5.3-codex` | OpenAI | 6x | Long-horizon agentic loops (hours+), cost-per-patch matters | Terminal-Bench 77.3%, SWE-Lancer IC 81.4% | Now eclipsed by 5.5 on Terminal-Bench | | `gpt-5.4-mini` | OpenAI | 6x | OSWorld/screenshot work | OSWorld 72.1% | **No longer cheap (6x now)** + long-context retrieval (MRCR 47.7% @64-128K). For bulk fan-out use the 0.33x models instead | | `gpt-5-mini` | OpenAI | **0.33x** | **Cheap default + bulk subagent fan-out** | — | Frontier reasoning | | `claude-opus-4.8` | Anthropic | 27x | **NEWEST Anthropic — multi-file production review, frontier blast-radius decisions** | Opus 4.8 flagship | Terminal-heavy work — gpt-5.5 wins | | `claude-opus-4.7` | Anthropic | 27x | Prior-gen Opus; multi-file review | SWE-Bench Pro **64.3%** (beat GPT-5.5's 58.6%) | Prefer 4.8 — same 27x cost | | `claude-sonnet-4.6` | Anthropic | 9x | Mid-tier; ~ what `Agent` tool `model: "sonnet"` invokes. **Top Sonnet on Copilot — NO Sonnet 5 here** | GDPval-AA 57% (beat gemini-3.1-pro's 40%) | Multi-file refactors where Opus fits | | `claude-sonnet-4.5` | Anthropic | 6x | Backward-compat against pre-4.6 Sonnet behavior | — | New work — pick 4.6 | | `claude-haiku-4.5` | Anthropic | **0.33x** | **Cheap: TTFT-critical interactive paths, parallel fan-out** | TTFT leader; GPQA 73.0% | Frontier reasoning | | `gemini-3.1-pro` | Google | 6x | Distributed-system reasoning, cross-doc consistency (Preview) | — | — | | `gemini-3.5-flash` | Google | 14x | Google-family fast reasoning | — | Cost-sensitive fan-out — 14x is pricey for a "flash" tier | | `mai-code-1-flash` | Microsoft | **0.33x** | **Cheap MS-native fan-out** (Microsoft MAI) | — | Frontier / high-stakes work | **Dropped from the 2026-07-01 picker** (were listed 2026-05-03 — probe before relying, likely retired): `gpt-5.2`, `gpt-5.2-codex`, `gpt-4.1`, `claude-sonnet-4`. Copilot keeps some backward-compat depth (`claude-sonnet-4.5`, `gpt-5.4-mini`) but the deep-legacy coverage narrowed. **New arrivals since 2026-05:** Claude Opus 4.8 (27x), Gemini 3.1 Pro (6x) / 3.5 Flash (14x), MAI-Code-1-Flash (0.33x). Note Copilot has **Opus 4.8 but not Sonnet 5** (top Sonnet is 4.6) — same Anthropic ceiling as droid on the Sonnet line, but unlike droid it does carry Opus 4.8. ### Picking a model — quick decision ``` Reading PRs/issues/code-search via GitHub MCP? → any of the above — pair with --add-github-mcp-toolset {issues|pulls|code-search|all} Frontier code review on diff touching money/auth/migration? → --model claude-opus-4.8 (newest; or claude-opus-4.7 — same 27x cost) OR --model gpt-5.5 (Terminal-Bench SOTA, 57x — priciest seat) Run BOTH on copilot for highest-stakes diffs. Independent second opinion on codex's gpt-5.5 verdict? → --model gpt-5.5 on copilot — same model, different harness = independent signal Bulk fan-out across N tasks? (cheapest = 0.33x) → --model gpt-5-mini OR --model claude-haiku-4.5 OR --model mai-code-1-flash ⚠ NOT gpt-5.4-mini — it is 6x now, no longer a cheap fan-out seat. Backward-compat testing — "did this old model handle it differently?" → copilot still exposes some prior-gen IDs (claude-sonnet-4.5, gpt-5.4-mini), but the 2026-07-01 picker DROPPED gpt-5.2, gpt-5.2-codex, gpt-4.1, claude-sonnet-4 — probe with `copilot --model -p ping` before relying on any legacy ID. ``` Verify availability before long runs: probe with `copilot --model -p "ping"`. Wrong IDs return clear errors immediately. ## Workflow ```dot digraph copilot_workflow { "Identify copilot-fittable task" -> "Verify copilot CLI auth"; "Verify copilot CLI auth" -> "Write task spec file"; "Write task spec file" -> "Pick effort level + GitHub MCP scope"; "Pick effort level + GitHub MCP scope" -> "Launch copilot -p"; "Launch copilot -p" -> "Wait for exit"; "Wait for exit" -> "Audit diff via subagent"; "Audit diff via subagent" -> "Run tests"; "Run tests" -> "Claude commits"; } ``` ### 1. Verify copilot is installed and authed ```bash which copilot && copilot --version echo "noop test" | copilot -p --allow-all "echo hello" --log-dir /tmp 2>&1 | tail -5 ``` If `which copilot` returns empty, copilot was not installed. Install the official CLI package at the exact version verified from npm registry metadata on 2026-07-14: `npm install -g @github/copilot@1.0.70`. The user must run `copilot login` themselves. ### 2. Write the task spec file Save at `/.claude/copilot_task_.md`. Same shape as use-codex / use-cursor / use-droid spec templates. **If task is a driver script for a long-running remote job:** cite your own job-driver conventions if you keep them documented, and require copilot to load + apply whatever environment-setup prerequisites (dependency pins, version upgrades) the target environment needs before the main work starts, so the job doesn't crash partway through. For GitHub-touching work add an extra section: ```markdown ## GitHub context (read-only via MCP) - Read issue # for the bug report - Read PR # for the prior fix attempt - Cross-reference branch `` with main: `gh pr view ` - Inspect Action run if the bug surfaced in CI ## GitHub actions allowed - ❌ Do NOT comment on PRs / issues - ❌ Do NOT close / merge / approve - ❌ Do NOT push branches - ✅ Read-only API calls only ``` ### 3. Launch copilot **Read-only audit pass:** ```bash nohup copilot \ --effort xhigh \ --add-dir / \ -p "Read .claude/copilot_task_.md and execute its instructions. Read-only — no file edits, no GitHub writes." \ --log-dir /tmp/copilot__logs \ > /tmp/copilot_.log 2>&1 & echo $! > /tmp/copilot_.pid ``` **Implementation pass with GitHub MCP enabled:** ```bash nohup copilot \ --effort high \ --allow-all-tools \ --add-dir / \ --add-github-mcp-toolset all \ -p "Read .claude/copilot_task_.md and execute every TODO. Edit files in-place. Do NOT git commit, git add, or git push. Print final summary line and exit." \ --log-dir /tmp/copilot__logs \ > /tmp/copilot_.log 2>&1 & ``` **Permission flags — pick the minimum that gets the work done:** | Flag | What it does | |---|---| | (default) | Read-only mode; copilot prompts on every edit | | `--allow-all-tools` | Tool calls run without confirmation. Required for `-p` non-interactive mode. | | `--allow-all-paths` | File-write paths not gated. Use only with `--add-dir ` to bound the worktree. | | `--allow-all-urls` | URL access ungated. Avoid unless the task requires fetching arbitrary URLs. | | `--allow-all` | All three above. **Same blast-radius as `--skip-permissions-unsafe` on droid.** Reserve for specs you wrote and trust. | Always pair `--allow-all-paths` (or `--allow-all`) with `--add-dir ` so paths outside the repo are still gated. ### 4. Wait for exit, then **layered audit**: subagent first, you second ```bash while kill -0 $(cat /tmp/copilot_.pid) 2>/dev/null; do sleep 30; done echo "exited" tail -60 /tmp/copilot_.log ls -la /tmp/copilot__logs/ # copilot writes per-tool logs here git diff --stat ``` Same layered review pattern as the other CLIs: 1. **Subagent audits copilot's diff first** — dispatch a `feature-dev:code-reviewer` Agent subagent with spec + diff. 2. **You audit the subagent's report + flagged hunks only** — don't re-read whole diff. 3. **If clean** — `git add` explicit files, commit, push. 4. **If subagent flags issues** — rewrite spec to be more explicit, relaunch copilot. ### 5. Tests + commit Run only the tests touching changed files. If clean: `git add` explicit files, commit with a message that credits copilot (`worker: copilot --effort high`), push. ## Prompt shape — required fields Same as the other use-* skills. ## Guardrails - **Never paste raw markdown into the `-p` argument** for non-trivial prompts. Reference a spec file path: `-p "Read and execute"`. Long inline prompts hit shell-quoting bugs and get truncated. - **No backticks in the `-p` string.** Reference the spec by path. - **`--add-dir` is the path-allowlist gate.** If you forget it but pass `--allow-all-paths`, copilot can write anywhere on the filesystem. Always pair them. - **GitHub MCP scope:** `--add-github-mcp-toolset all` is convenient but exposes write tools too. For audit-only passes, omit it or pass an explicit subset like `--add-github-mcp-toolset issues --add-github-mcp-toolset pulls`. - **Process pollution check:** `ps -ef | grep -E "copilot" | grep -v grep` - **Don't trust copilot's success report alone.** Audit diff + run tests yourself. - **Log dir:** always pass `--log-dir ` so per-tool traces are recoverable. Default location is platform-dependent and gets noisy. ## When to escalate / abort - Copilot exits non-zero or prints a `BLOCKER` → tail log, diagnose, possibly rewrite spec + relaunch - Copilot edits files outside the "Edits required" scope → revert via `git checkout -- `, narrow spec - Copilot commits despite no-commit constraint → `git reset --soft HEAD~1` to keep work, audit, re-commit cleanly - Copilot stalls past expected wall → `kill $(cat /tmp/copilot_*.pid)`, inspect log, decide whether to retry ## Routing — when copilot beats codex / gemini / cursor / droid | Situation | Pick | |---|---| | Read PR/issue context as part of the task | **copilot** (built-in GitHub MCP) — others need MCP setup | | Use Copilot subscription you already pay for | **copilot** (no per-task billing) | | Cross-org repo navigation via code search | **copilot** (GitHub MCP code-search) | | Frontier peer review on diff that touches money/auth/migration | **codex** (gpt-5.5) — cleaner single-model SOTA review | | Distributed-system reasoning / cross-doc consistency | **gemini** (3.1-pro plan-mode, dead post-2026-06-18 -> use agy/droid) — different blind spots | | Multi-file content write ≥3 files | **cursor** (unlimited tokens, auto-mode) | | Multi-agent mission worker+validator | **droid** (--mission) — only CLI with this primitive | | Cross-provider second opinion in one tool | **droid** (-m switching) | ## Cross-references - Sibling skills: `use-codex`, `use-gemini`, `use-cursor`, `use-droid` - If you run a multi-seat review orchestrator, it can combine all of the above into a single multi-stage deliberation. - Evidence-backed model picker: keep your own model-task benchmark notes if you maintain them, and cite the doc here.