The Grammar of Coding Agents

OpenAI Codex, Claude Code, OpenCode, Cursor, and GitHub Copilot

Snapshot verified: June 19, 2026Scope: Interactive command languages, context sigils, skills, subagents, planning, review, insights, and differences between terminal, desktop, IDE, and cloud harnesses.

This is a living reference. Command availability can vary by version, operating system, plan, experimental flags, and connected extensions. In every harness, typing

/

in the active composer is the best final check for what is available in that exact installation.

Executive summary #

The five product families increasingly share the same building blocks - slash commands, reusable skills, project instructions, MCP, custom agents, shell execution, and context management - but they expose them through different command languages.

Codex has the clearest use of$

:$skill-name

explicitly invokes a skill, while$app-slug

attaches an app/connector.@

is primarily workspace/file context, though recent Codex releases are moving toward a unified mentions menu. Codex has/goal

, but parallel subagents are requested in natural language rather than through/fleet

.Claude Code has the broadest built-in command catalog and the richest collection of packaged workflows. Skills are invoked as/skill-name

, not with$

. Its stand-out commands include/insights

,/batch

,/code-review

,/loop

,/ultraplan

, and/workflows

.OpenCode has a smaller built-in slash-command surface but a very flexible customization model.@

can reference both files and agents; custom commands support$ARGUMENTS

,$1

,$2

, shell-output injection, file references, agent selection, and forced subtask execution.Cursor combines an IDE, terminal CLI, and Cloud Agents around one rules, skills, MCP, and subagent system. Skills and custom subagents use/name

;@

attaches files, folders, docs, terminals, prior chats, diffs, browser state, and manual rules. Cursor CLI uses/shell

rather than a documented!

shortcut, and& prompt

hands a local CLI task to a Cloud Agent.GitHub Copilot must be split by harness. Copilot CLI and the Copilot app use a modern agent runtime with/fleet

,/chronicle

,/research

, skills, plugins, and custom agents. VS Code Chat uses a different interaction model centered on/explain

,/fix

,#file

, and@workspace

. GitHub.com Chat has another, smaller set of conversation commands and@

attachments.

How to read the comparison

The closest equivalents are:

Intent	Codex	Claude Code	OpenCode	Cursor	GitHub Copilot CLI
Persistent objective	/goal
Natural language, plan/workflow; no direct equivalent	Natural language; no direct equivalent	Plan/checkpoints; no persistent /goal object
Plan/autopilot; no direct /goal equivalent
Plan before editing	/plan
/plan or /ultraplan
Switch to Plan agent
Plan mode: Shift+Tab , /plan , or --mode=plan
/plan ; Shift+Tab can select plan mode
Parallel subagents	Ask explicitly: “spawn agents in parallel”	/batch , subagents, agent teams, workflows
@subagent , automatic delegation, or subtask: true
Automatic or /subagent-name ; ask for parallel work; /best-of-n uses worktrees
/fleet
Inspect agent workers	/agent
/agents , /tasks , claude agents
Child-session navigation	Agent UI; background output under ~/.cursor/subagents/ ; Cloud Agents dashboard
/tasks , /agents , /subagents
Session insights	/usage , /status ; no /insights equivalent
/insights , /usage , /team-onboarding
No built-in equivalent	/context ; team analytics, but no personal /insights equivalent
/chronicle , /usage
Code review	/review , /diff
/code-review , /review , /security-review , /simplify
Plan/review agent or custom command	CLI Ctrl+R ; Agent /review or /review-bugbot ; Bugbot PR review
/review , /security-review , /diff , /pr
Explicit skill	$skill-name or /skills picker
/skill-name
Agent loads through the skill tool
/skill-name
/skill-name ; manage with /skills
File context	@path , /mention
@path
@path
@file , @folder , @Docs , @Terminals , @Past Chats , diffs, browser
CLI: @path ; VS Code: #file ; GitHub.com: @ attachment
Direct shell	!command
!command
!command
CLI /shell command , /sh , or /run ; no documented ! shortcut
!command ; ! alone enters shell mode

1. The sigils: what / #

, @

, $

, #

, and !

mean

Sigil	Codex	Claude Code	OpenCode	Cursor	GitHub Copilot
/
Built-in session commands; enabled skills also appear in the list	Built-in commands, bundled skills, user skills, plugin skills, MCP prompts	Built-in and user-defined custom commands	CLI commands, Agent Skills, custom subagents, and product workflows such as /worktree and /review
CLI: full runtime commands and skills. VS Code/GitHub.com: surface-specific chat commands
@
Stable docs: fuzzy workspace/file mention. Recent releases also expose a broader unified mention menu	File mention in normal sessions; in agent view it can target a custom agent or sibling repository	File/reference mention and subagent mention	Files/folders, docs, terminals, past chats, Git diffs, browser context, and manually applied rules	CLI: file context. VS Code: chat participants such as @workspace . GitHub.com: attach repos, issues, PRs, files, and extensions. Fleet prompts can name @custom-agent
$
First-class interactive syntax: $skill-name and $app-slug
Not the normal invocation sigil. $ARGUMENTS and positional variables are used inside skill/command definitions
Not the normal invocation sigil. $ARGUMENTS , $1 , $2 , and so on are custom-command template variables
No primary interactive $ convention; ordinary shell environment variables still use $VAR
No primary interactive $ convention. Skills use /skill-name ; shell/environment configuration may still contain ordinary $VAR syntax
#
No primary interactive context convention	In agent view, #123 can identify an existing PR session
No primary interactive context convention	No primary interactive context convention documented	CLI: #123 attaches a GitHub issue or PR. VS Code: #file , #selection , #project , and other chat variables
!
Run a local shell command and add the result to context, subject to sandbox/approval rules	Enter shell mode for one command; output enters context	Run a shell command; output enters context	No documented ! shortcut; Cursor CLI uses /shell , /sh , or /run
Run a local shell command bypassing Copilot. ! alone enters multi-command shell mode

Sigil portability at a glance

Practical consequence

The most dangerous portability mistake is assuming the same sigil means the same thing:

@workspace

is a Copilot VS Code participant, not a portable way to request repository context elsewhere.$frontend-design

is a Codex skill invocation, but Claude Code and Copilot normally expect/frontend-design

.$ARGUMENTS

in Claude Code and OpenCode belongs inside the reusable command definition; it is not how an end user invokes the command.#file

is Copilot vocabulary. Codex, Claude Code, and OpenCode normally use@file

.- Cursor uses /skill-name

and/subagent-name

; its@

menu is for context and manual rules, not the primary custom-agent selector.

2. Capability comparison #

Legend: Yes = directly documented; Partial = available through another mechanism or only some surfaces; No = no close built-in equivalent documented.

Capability	Codex	Claude Code	OpenCode	Cursor	Copilot CLI	Copilot VS Code Chat
Rich built-in slash-command catalog	Yes	Yes - largest catalog	Partial - compact built-in set	Yes in CLI; editor also exposes skills and workflow commands	Yes	Partial - task shortcuts
User-defined slash commands	Legacy custom prompts are deprecated in favor of skills	Yes; custom commands merged into skills	Yes; highly configurable command templates	Skills replace older commands; /migrate-to-skills converts them
Yes through skills/plugins	Yes through .prompt.md prompt files
Agent Skills (SKILL.md )
Yes	Yes	Yes	Yes; reads Cursor, Agent, Claude, and Codex skill directories	Yes	Yes in agent mode
Explicit skill syntax	$skill-name
/skill-name
No dedicated user sigil documented; agent uses skill tool	/skill-name
/skill-name
Prompt files use /name ; Agent Skills can be selected/invoked by the agent
Implicit skill selection	Yes	Yes	Yes	Yes unless disable-model-invocation: true
Yes	Yes in agent mode
Project instructions	AGENTS.md
CLAUDE.md
AGENTS.md
.cursor/rules/*.mdc , AGENTS.md ; CLI also reads root CLAUDE.md
.github/copilot-instructions.md , AGENTS.md , and related instruction files
Same Copilot instruction system
Custom agents	Yes	Yes	Yes	Yes: .cursor/agents , with Claude/Codex-compatible locations
Yes	Yes
Named agent selection	Configure agents; ask in prompt; /agent switches spawned threads
/agents , --agent , agent view @agent
Tab for primary agents; @subagent
/subagent-name or natural language; automatic delegation
/agent , --agent , natural language
Agent picker/custom agents
Parallel worker command	No dedicated /fleet ; ask explicitly
/batch ; also teams/workflows
No dedicated fleet command; delegation and subtasks	Ask for parallel work; multiple Task calls; /best-of-n for parallel worktrees
/fleet
Agent mode supports subagents, but not the CLI /fleet vocabulary
Persistent goal object	/goal
No direct equivalent	No direct equivalent	No direct equivalent	No direct equivalent	No direct equivalent
Planning mode	/plan
/plan , /ultraplan
Built-in Plan agent	Editor Plan mode; CLI /plan , --plan , --mode=plan
/plan , plan mode
Plan mode
Side question without polluting main history	/side or /btw
/btw
Start/switch session	Ask mode: /ask or --mode=ask
/ask experimental
Start a new chat or use another chat surface
Built-in insights from history	No dedicated /insights
/insights
No	/context ; team analytics only
/chronicle
Synced agent-session search; no equivalent VS Code slash command
Built-in deep research	Web search/tools; no dedicated slash command in core catalog	/deep-research
Tools/custom agents	Explore subagent and web search tools; no dedicated research slash command documented	/research
@github #web for web-enabled questions
Built-in code review	/review
Multiple review workflows	Custom/review agent pattern	CLI Ctrl+R ; /review , /review-bugbot , and Bugbot PR review
/review , /security-review
Review actions and Copilot code review
Scheduled prompts	Codex app automations	/loop , routines/workflows
Plugins/external scheduling	No comparable built-in scheduler documented	/every , /after experimental
Not the same interactive mechanism
Session rollback with file restoration	Git-based inspection; no general /undo in the app catalog
/rewind //undo
/undo and /redo require Git
Editor checkpoints; CLI /rewind
/undo //rewind , tool-layer tracking
Checkpoints in supported agent modes
MCP	Yes	Yes	Yes	Yes across editor, CLI, and Cloud Agents	Yes, GitHub MCP built in	Yes
Plugins	Yes	Yes	Yes	Yes; CLI /plugin and marketplaces
Yes	Extensions/customizations, but not identical to CLI plugins
Local sandbox/permissions	Yes	Yes	Yes	Yes; CLI /sandbox , permissions and approval modes
Yes	Workspace trust and agent tool approvals
Cloud delegation	Codex Cloud	Claude Code on the web	Self-hosted server/web; provider-dependent	Cloud Agents; CLI & prompt ; local /in-cloud subagent
/delegate , --cloud , cloud agent
Can delegate to Copilot cloud agent

3.OpenAI Codex #

Harnesses

Harness	Best use	Command-language notes
Codex CLI
Terminal-native local work, scripting, shell-heavy debugging, subagents	Richest Codex slash catalog; @ , $ , and ! are all meaningful
Codex app
Parallel threads, worktrees, automations, Git review, artifacts	Smaller slash list, visual project/session management, shared skills
Codex IDE extension
Editor context, selections, local/cloud handoff	Surface-specific /local , /cloud , /auto-context ; shared config with CLI
Codex Cloud/web
Background work in configured cloud environments	Usually delegated from app, IDE, CLI, or web rather than controlled through the full local slash catalog

High-value Codex CLI commands

Category	Commands
Project/session	/init , /new , /resume , /fork , /archive , /delete , /clear , /title
Context	/compact , /status , /usage , /memories , /mention
Work control	/plan , /goal , /side , /btw , /ps , /stop
Agents/extensions	/agent , /skills , /apps , /plugins , /hooks , /mcp , /import
Model/behavior	/model , /fast , /personality , /permissions , /experimental
Review/output	/diff , /review , /copy , /raw , /theme , /statusline
Account/support	/feedback , /logout , /debug-config , /exit , /quit

Codex app slash commands

/feedback

, /goal

, /init

, /mcp

, /plan

, /review

, /status

Codex IDE extension slash commands

/auto-context

, /cloud

, /cloud-environment

, /feedback

, /goal

, /local

, /review

, /status

Skills, apps, and context

• Use $skill-name

to explicitly invoke a skill. - Use /skills

to browse available skills; enabled skills also appear in the slash menu. /apps

inserts a connector as$app-slug

.- Use @path

or/mention

for file context. - Use !command

for a local shell command.

Subagent behavior

Codex supports parallel subagents in the CLI and app, but the trigger is an explicit natural-language request rather than /fleet

. For example:

Spawn three subagents in parallel: one for security, one for test gaps,
and one for maintainability. Wait for all three and merge the findings.

/agent

does not itself mean “start a fleet”; it switches between already spawned agent threads.

Distinctive strengths

• Persistent /goal

state with /resume/clear behavior. - First-class $

syntax for skills and apps. - Tight local/cloud handoff across CLI, app, and IDE.

• App-centric parallel threads, worktrees, automations, artifact previews, and Git review.

4.Claude Code #

Harnesses

Claude Code is available in the terminal, IDE, desktop app, and browser. Anthropic describes the CLI as the most complete surface; desktop and IDE trade some CLI-only capabilities for visual review and tighter editor integration.

High-value Claude Code commands

Category	Commands
Setup/config	/init , /memory , /mcp , /permissions , /agents , /skills , /config , /model , /effort
Planning	/plan , /ultraplan , /advisor
Parallel work	/agents , /tasks , /background , /batch , /fork , /workflows
Context/session	/context , /compact , /btw , /clear , /resume , /branch , /teleport , /remote-control
Review/verification	/diff , /code-review , /review , /security-review , /simplify , /verify
Research/diagnosis	/deep-research , /debug , /doctor
Automation	/loop , /workflows , /autofix-pr
Insights/usage	/insights , /usage , /stats , /team-onboarding

Commands that are especially distinctive

/insights

analyzes Claude Code sessions for project areas, interaction patterns, and friction points./batch

decomposes a large change into roughly 5-30 worktree-isolated subagents, each expected to implement, test, and open a pull request./code-review

can review, fix, comment on a PR, or run an ultra cloud review./simplify

runs multiple cleanup-oriented review agents./loop

runs a repeated or self-paced task./ultraplan

and/ultrareview

connect terminal work to deeper cloud planning/review./team-onboarding

analyzes recent usage and generates a teammate onboarding guide.

Skills and custom commands

• Invoke a skill as /skill-name

. - User skills live under .claude/skills/<name>/SKILL.md

. - Older .claude/commands/*.md

files still work, but Anthropic now treats custom commands as skills. $ARGUMENTS

and positional parameters are used inside skill definitions.- MCP prompts appear as /mcp__<server>__<prompt>

.

Context and shell syntax

@path

opens file-path autocomplete and attaches file context.!command

runs a command directly and adds its output to the conversation.- In the multi-agent view, @agent-name

can choose a custom agent and@repo

can target a sibling repository.

Subagent choices

Claude Code has several distinct parallelism mechanisms:

Subagents for isolated delegated tasks.Agent view(claude agents

) for multiple background sessions.Agent teams for coordinated sessions that communicate.Dynamic workflows for background multi-phase orchestration.as a packaged large-change workflow using worktrees and subagents./batch

Distinctive strengths

• The broadest command vocabulary.
• Strong history analysis through /insights

. - Several levels of parallel execution, from one-off subagents to teams and workflows.

• Rich packaged workflows for review, debugging, research, verification, onboarding, and scheduling.

5.OpenCode #

Harnesses

OpenCode is available as a TUI, desktop app, IDE extension, and browser application. It also supports ACP clients. ACP carries most OpenCode capabilities, although some built-in commands such as /undo

and /redo

are not supported there.

Built-in TUI commands

Command	Purpose
/connect
Add/configure a model provider
/compact or /summarize
Compact the current session
/details
Toggle tool-execution detail
/editor
Compose in an external editor
/exit , /quit , /q
Exit
/export
Export the conversation to Markdown
/help
Open help
/init
Create or update AGENTS.md
/models
Select/list models
/new or /clear
Start a new session
/redo
Restore an undone turn and file changes
/sessions , /resume , /continue
Browse and switch sessions
/share , /unshare
Publish or remove a shared session
/themes
Select a theme
/thinking
Show or hide reasoning blocks
/undo
Revert the latest turn and file changes

Custom commands

OpenCode's small built-in list is offset by a strong custom-command format:

• Define Markdown commands in .opencode/commands/

. - Use $ARGUMENTS

,$1

,$2

, and so on for parameters. - Inject shell output into a command prompt.

• Include files with @path

. - Pin a command to an agent or model.

• Set subtask: true

to force the command into a separate subagent context. - A custom command can override a built-in command with the same name.

Example:

---
description: Review one component
agent: plan
subtask: true
---

Review @$1 for correctness, accessibility, and performance.
Run the smallest relevant tests and summarize the risks.

Agents

• Primary agents: Build andPlan. - Switch primary agents with Tab

or the configured agent-switch key. - Built-in subagents: General,** Explore**, and** Scout**. - Invoke a subagent directly with @general

,@explore

, or@scout

. - Primary agents may also delegate automatically based on subagent descriptions.

Skills

OpenCode supports SKILL.md

skills and searches .opencode/skills

, .claude/skills

, and .agents/skills

at project and user scope. Skills are discovered by metadata and loaded on demand through the native skill

tool.

Context and shell syntax

@path

attaches a file or configured reference.@agent

can invoke a subagent.!command

runs a shell command and adds the result to context.$...

is primarily template syntax inside custom commands, not a first-class end-user skill selector.

Distinctive strengths

• Provider-agnostic and open source.
• Very clean Build/Plan split.
• Custom commands can select model, agent, and subtask behavior.
• Compatibility with Claude-style and Agent Skills directories makes it easy to share reusable behavior.

6.Cursor #

Cursor is best understood as a family of connected harnesses rather than only an editor. The editor, terminal CLI, Agents Window, Cloud Agents, and Bugbot share rules, skills, MCP configuration, custom subagents, and session context to different degrees.

Harnesses

Harness	Best use	Command-language notes
Cursor editor Agent
Repository work with visual diffs, checkpoints, browser context, and IDE tools	Rich @ context menu; skills and subagents use /name ; Plan and Ask modes are built in
Cursor CLI
Terminal-native agent work and automation	Large slash catalog, @file /@folder , /shell , headless mode, sessions, worktrees, and cloud handoff
Agents Window
Running several local agents independently	Native worktree isolation, parallel sessions, review, and applying completed work
Cloud Agents
Remote background work from web, desktop, mobile, integrations, or CLI	Runs in isolated remote environments and branches; CLI handoff uses & prompt
Bugbot
Pull-request review and autofix	Reviews PRs in GitHub or Bitbucket and can launch a Cloud Agent to fix findings

High-value Cursor CLI commands

Category	Commands
Modes	/plan , /ask , /debug , /run-everything , /max-mode
Session/context	/clear , /resume , /fork , /summarize , /context , /rewind , /rename
Display/control	/vim , /line-numbers , /show-thinking , /status-indicators , /logs
Shell/editor	/shell , /sh , /run , /open , /cursor , /setup-terminal
Models/extensions	/model , /mcp , /plugin , /config , /sandbox , /bedrock
Support/account	/about , /help , /feedback , /copy-request-id , /copy-conversation-id , /logout , /quit

Cursor CLI also supports:

agent -p

oragent --print

for non-interactive output.--force

or--yolo

when a headless run is allowed to modify files.--worktree [name]

or-w

for an isolated worktree.agent ls

,agent resume

,--continue

, and--resume=<id>

for session recovery.agent acp

when Cursor is used through an ACP-compatible host.

Context, plans, and worktrees

• Use @file

or@folder

to attach repository context. - The editor also exposes @Docs

,@Terminals

,@Past Chats

, Git working-state or branch diffs, and@Browser

. - Plan mode is available from Shift+Tab

,/plan

,--plan

, or--mode=plan

. - Ask mode is available as /ask

or--mode=ask

. - The editor supports /worktree

,/best-of-n

,/apply-worktree

, and/delete-worktree

; the CLI uses--worktree

. - In the CLI, Ctrl+R

opens a review of the agent's changes.

Skills and rules

• Skills use SKILL.md

and can be selected automatically or explicitly as/skill-name

. disable-model-invocation: true

makes a skill explicit-only.- Cursor discovers skills from .agents/skills

,.cursor/skills

,.claude/skills

, and.codex/skills

, including supported user-level locations. /migrate-to-skills

converts older command-style customizations.- Project rules live in .cursor/rules/*.mdc

; Cursor also supportsAGENTS.md

, user rules, and team rules. - A manually applied rule can be attached with @rule-name

;/create-rule

helps create a rule.

Subagents

• Cursor can delegate automatically based on a subagent's description.
• Explicit invocation uses /subagent-name

or a natural-language request. - Multiple independent subagent tasks can run in parallel.

• Built-in subagents include Explore,** Bash**, and** Browser**. - Custom agents live in .cursor/agents

; Cursor also reads compatible.claude/agents

and.codex/agents

locations. - Agent definitions can specify a model, read-only behavior, and background execution.

• Background subagent output is stored under ~/.cursor/subagents/

.

Cloud handoff and review

• Prefix a Cursor CLI prompt with &

to send it to a Cloud Agent. /in-cloud

sends the next delegated task to a cloud subagent./babysit

monitors and helps shepherd a pull request./review

and/review-bugbot

are documented for Cursor Agent and cursor.com/agents in Cursor 3.7 and later. Cursor's documentation currently says CLI support is coming later.- Bugbot Autofix can create a Cloud Agent task from a review finding.

Distinctive strengths

• One customization model spans editor, CLI, local agents, and cloud agents.
• The richest @

context vocabulary in this comparison. - Explicit /skill-name

and/subagent-name

syntax keeps reusable behavior easy to discover. - Native local worktrees, best-of-N execution, cloud handoff, PR review, and browser-aware work.

7.GitHub Copilot: compare the harnesses separately #

Copilot's surfaces are not one command language

7.1GitHub Copilot CLI

Copilot CLI now has a large terminal-agent command surface.

Category	Commands and shortcuts
Planning/autonomy	/plan , Shift+Tab for standard/plan/autopilot, --autopilot
Parallelism	/fleet , /tasks , /agents , /subagents , custom agents
Insights/history	/chronicle , /usage , /context , /session , /resume
Research/review	/research , /review , /security-review , /rubber-duck , /diff
GitHub workflow	/pr , /delegate , #123 issue/PR context
Skills/plugins	/skills , /plugin , invoke /skill-name
Runtime/config	/model , /mcp , /lsp , /permissions , /sandbox , /settings , /env
Scheduling	/every , /after in experimental mode
Session control	/compact , /clear , /ask , /worktree , /remote , /app , /ide
Direct context/shell	@file , #issue-or-PR , !command

/fleet

/fleet

decomposes work and runs independent subtasks in parallel. Copilot can choose custom agents for subtasks, and you can name one in the prompt with @custom-agent-name

.

/fleet Implement the API validation, add integration tests, and update the docs.
Use @test-writer for the test work.

/chronicle

/chronicle

is Copilot CLI's closest equivalent to Claude Code's /insights

.

Documented subcommands include:

standup

• summarize recent work.tips

• personalized workflow suggestions.cost tips

• token-spend feedback.search

• search session history.improve

• suggest improvements to custom instructions.reindex

• rebuild and synchronize the session store.

The exact short form shown by /help

may vary as the feature evolves.

Skills

• Copilot may automatically select skills.
• Explicitly request one with /skill-name

. - Manage them with /skills list

,/skills info

,/skills add

,/skills remove

, and/skills reload

.

7.2GitHub Copilot app

The desktop app is built on the Copilot CLI runtime and is designed for managing multiple local and cloud agent sessions. It shares session-history data with the CLI and can contribute to /chronicle

reports.

Important distinction: runtime sharing does not guarantee that every CLI slash command is exposed identically in every app composer. Use the app's live /

menu as the authoritative list.

Best fit:

• Multiple concurrent agent sessions.
• Visual session management.
• GitHub-native repository, branch, CI, issue, and PR workflows.
• MCP servers configured from repositories, CLI configuration, or app settings.

7.3Copilot Chat on GitHub.com

GitHub.com Chat uses a lighter command language:

/clear

,/delete

,/new

,/rename

.@

attaches discussions, extensions, files, issues, pull requests, and repositories.- GitHub MCP skills can perform repository operations from natural language.

This is a GitHub-object chat surface, not a local terminal harness.

7.4Copilot Chat in VS Code

Common slash commands:

/clear

, /explain

, /fix

, /fixTestFailure

, /help

, /new

, /tests

Common chat variables:

#block

, #class

, #comment

, #file

, #function

, #line

, #path

, #project

, #selection

, #sym

Common chat participants:

@azure

, @github

, @terminal

, @vscode

, @workspace

Useful query patterns:

@workspace Explain the authentication flow and identify the trust boundaries.
#file:src/auth.ts /tests Generate tests for the token refresh edge cases.
@github #web What is the current supported Node.js LTS, and what changes would
this repository need to upgrade?

Prompt files under .github/prompts/*.prompt.md

create reusable /prompt-name

commands in supported IDEs.

7.5Copilot cloud agent

Copilot cloud agent runs independently in a GitHub-hosted environment, works on a branch, and can create a pull request. It can be started from GitHub, mobile, IDEs, API, GitHub CLI, the GitHub MCP Server, and external work-management integrations.

Do not confuse:

IDE agent mode: acts in the local workspace.Copilot cloud agent: acts in a managed GitHub environment.Copilot CLI: acts locally unless explicitly delegated or started with a cloud mode.

8. Query translation guide #

What you want	Codex	Claude Code	OpenCode	Cursor	Copilot CLI	Copilot VS Code
Explain one file	Explain @src/auth.ts
Explain @src/auth.ts
Explain @src/auth.ts
Explain @src/auth.ts
Explain @src/auth.ts
#file:src/auth.ts /explain
Plan first	/plan Add passkeys
/plan Add passkeys
Switch to Plan, then ask	/plan Add passkeys or select Plan mode
/plan Add passkeys
Select Plan mode
Run three reviews in parallel	Ask to spawn three subagents	Ask for parallel subagents or use a workflow	Mention subagents or create subtask: true commands
Ask for parallel subagents or use /best-of-n
/fleet ...
Ask Agent mode to delegate/subagent if available
Invoke a design skill	$frontend-design ...
/frontend-design ...
Ask the agent to load the skill, or wrap it in a custom command	/frontend-design ...
/frontend-design ...
Use the Agent Skill or a /prompt-file
Review current changes	/review , then /diff
/code-review or /review
Use Plan/review agent or custom /review
CLI Ctrl+R ; Agent /review or /review-bugbot
/review , /diff
Use code review/agent actions
Get usage coaching	/usage
/insights and /usage
No built-in equivalent	/context ; team analytics are separate
/chronicle tips , /chronicle cost tips
Query synced sessions or use usage views
Run a shell command	!npm test
!npm test
!npm test
/shell npm test
!npm test
Use terminal participant/tooling
Start fresh	/new
/clear
/new
/clear or /new
/new
/clear

9. Recommendations by working style #

Working style	Best fit from this comparison	Why
Terminal power user who wants the broadest packaged workflow catalog	Claude Code	Deep command catalog, /insights , /batch , review and workflow commands
User who wants a persistent objective and a strong desktop multi-thread workspace	Codex	/goal , parallel app threads, worktrees, automations, artifacts
Open-source, provider-agnostic user who likes building custom commands	OpenCode	Flexible command templates, agent selection, subtask routing, provider choice
IDE-first user who wants rich context, local parallelism, and easy cloud handoff	Cursor	Deep @ context, skills and subagents, worktrees, Cloud Agents, Bugbot
GitHub-centered user who wants issues, PRs, session history, parallel workers, and IDE integration	GitHub Copilot	/fleet , /chronicle , /pr , cloud agent, GitHub object context
User who wants a consistent Agent Skills investment across tools	All five, with caveats	All support SKILL.md ; invocation syntax and supported extensions differ

10. Other coding agents and harnesses to add later #

This is a candidate backlog, not an exhaustive market inventory.

Terminal-first or terminal-capable

Google Antigravity CLI- Google's consumer successor to Gemini CLI, sharing an agent harness with Antigravity 2.0, IDE, and SDK surfaces** AiderAmpCline CLIContinue CLICrushPlandexPi Coding AgentGooseJunie CLIKiro CLIFactory Droid**

IDE/editor-first

Devin Desktop / Cascade(the product formerly known as Windsurf)** ClineRoo CodeContinueJetBrains JunieKiro IDEZed Agent PanelAugment Code****Replit Agent**

Cloud/issue-to-PR and engineering-agent platforms

DevinOpenHandsFactoryGitLab Duo Agent PlatformReplit AgentAugment Remote AgentsWarp cloud agents / agent control plane

Useful adjacent harness hosts

Warp- can run its own agent and host external CLI agents.** Zed with ACP**- editor host for external agents.** VS Code Agent mode**- a harness layer that can host Copilot and third-party agents.

Recommended next comparison rows

For the next revision, the most useful additions would be:

Google Antigravity- compare its CLI, IDE, Antigravity 2.0 desktop command center, SDK, shared multi-agent harness, skills, hooks, plugins, and asynchronous subagents.Cline and Roo Code- model-agnostic VS Code agents with modes, rules, MCP, and skills.** Aider**- mature terminal command language and Git-centered workflow.** Kiro and Junie**- spec-driven and JetBrains-native agent approaches.** Devin, Factory, and OpenHands**- cloud/autonomous engineering-agent category.

11. Maintenance protocol #

When updating this report:

• Record the verification date at the top.
• Re-check each product's official command reference and live /

menu. - Separate stable, preview, and experimental commands.

• Keep GitHub Copilot surfaces in separate rows.
• Keep Cursor editor, CLI, Agents Window, Cloud Agents, and Bugbot distinctions explicit.
• Verify whether a command is a built-in command, a bundled skill, a custom skill, an MCP prompt, or a UI action.
• Re-check the meanings of /

,@

,$

,#

, and!

. - Update the “other agents” backlog for renames, retirements, and replacements.

• Add a short change-log entry below.

Change log

Date	Change
2026-06-20	Replaced the contents hamburger/close pair with restrained sidebar-state icons; moved the divider beneath the Contents heading; and excluded the document title from scroll-spy highlighting.
2026-06-20	Added a reusable content-aware SVG file icon that synchronizes its paper, ink, and accent colors with the active document theme and palette.
2026-06-20	Added local variable-font delivery, responsive WebP hero images with intrinsic dimensions, and a Brotli/Gzip static audit server following a Lighthouse performance pass.
2026-06-20	Moved the contents, light/dark, and color-palette controls into circular document-corner controls; added a desktop contents hide/show state with a menu-to-close icon transition.
2026-06-19	Added a generated llm.txt Markdown representation, a canonical llms.txt discovery index, HTML alternate-resource metadata, and discoverable footer links.
2026-06-19	Restored the original compact command-grammar hero, removed its chroma-key background and outer canvas padding, simplified heading typography, and rebuilt the Open Graph card around three text levels and a fading right-side illustration.
2026-06-19	Refined and moved the hero illustration above the title, added mobile-specific diagram compositions, and added Open Graph and Twitter sharing metadata with a dedicated 1200 × 630 social card.
2026-06-19	Added an opening line illustration and SVG diagrams for the four-layer request model, sigil portability, and GitHub Copilot harness boundaries.
2026-06-19	Replaced the consumer-facing Gemini CLI backlog entry with Google Antigravity. Consumer Gemini CLI service ended June 18, 2026; enterprise and paid API-key access remain supported.
2026-06-19	Added Cursor editor, CLI, Agents Window, Cloud Agents, Bugbot, skills, subagents, rules, worktrees, command translations, and official sources.
2026-06-19	Initial report. Added Codex, Claude Code, OpenCode, Copilot CLI, Copilot app, GitHub.com Chat, VS Code Chat, cloud-agent distinctions, sigil comparison, and future-agent backlog.

Sources #

All core comparisons use official documentation current on June 19, 2026.

OpenAI Codex

Codex CLI slash commandsCodex app commandsCodex IDE slash commandsCodex Agent SkillsCodex subagentsCodex CLI featuresCodex app features

Claude Code

Claude Code commandsClaude Code skillsClaude Code subagentsClaude Code parallel agentsClaude Code interactive modeClaude Code platforms

OpenCode

Cursor

Cursor Agent overviewCursor prompting and@

contextCursor Plan modeCursor CLI overviewUsing Cursor CLICursor CLI slash-command referenceCursor Agent SkillsCursor subagentsCursor Cloud AgentsCursor rulesCursor BugbotCursor worktrees

GitHub Copilot

Copilot CLI command referenceCopilot Chat cheat sheetCopilot CLI fleetCopilot CLI session data and ChronicleCopilot CLI Agent SkillsGitHub Copilot appCopilot cloud agentCopilot customization cheat sheet

source & further reading

grammar-of-coding-agents.pages.dev — original article