MCP Server Builder
anthropics/skills
Guides the design and implementation of Model Context Protocol servers in TypeScript or Python, from tool naming and error messages to evaluation.
Take a screenshot of a URL or the current page. An agent skill from mozilla/firefox-devtools-mcp.
$ npx skills add mozilla/firefox-devtools-mcp --skill screenshot -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install mozilla/firefox-devtools-mcp screenshot --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/mozilla/firefox-devtools-mcp.git skills-src && mkdir -p .claude/skills && cp -r skills-src/plugins/firefox-devtools-mcp/skills/screenshot .claude/skills/screenshot && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "screenshot" agent skill from https://github.com/mozilla/firefox-devtools-mcp/tree/main/plugins/firefox-devtools-mcp/skills/screenshot into .claude/skills/screenshot/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "screenshot", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/mozilla/firefox-devtools-mcp/tree/main/plugins/firefox-devtools-mcp/skills/screenshotType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add mozilla/firefox-devtools-mcp --skill screenshot -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install mozilla/firefox-devtools-mcp screenshot --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mozilla/firefox-devtools-mcp.git skills-src && mkdir -p .agents/skills && cp -r skills-src/plugins/firefox-devtools-mcp/skills/screenshot .agents/skills/screenshot && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "screenshot" agent skill from https://github.com/mozilla/firefox-devtools-mcp/tree/main/plugins/firefox-devtools-mcp/skills/screenshot into .agents/skills/screenshot/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "screenshot", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add mozilla/firefox-devtools-mcp --skill screenshot -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install mozilla/firefox-devtools-mcp screenshot --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mozilla/firefox-devtools-mcp.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/plugins/firefox-devtools-mcp/skills/screenshot .cursor/skills/screenshot && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "screenshot" agent skill from https://github.com/mozilla/firefox-devtools-mcp/tree/main/plugins/firefox-devtools-mcp/skills/screenshot into .cursor/skills/screenshot/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "screenshot", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/mozilla/firefox-devtools-mcp.git --path plugins/firefox-devtools-mcp/skills/screenshot--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add mozilla/firefox-devtools-mcp --skill screenshot -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install mozilla/firefox-devtools-mcp screenshot --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mozilla/firefox-devtools-mcp.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/plugins/firefox-devtools-mcp/skills/screenshot .gemini/skills/screenshot && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "screenshot" agent skill from https://github.com/mozilla/firefox-devtools-mcp/tree/main/plugins/firefox-devtools-mcp/skills/screenshot into .gemini/skills/screenshot/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "screenshot", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install mozilla/firefox-devtools-mcp screenshotInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add mozilla/firefox-devtools-mcp --skill screenshot -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/mozilla/firefox-devtools-mcp.git skills-src && mkdir -p .github/skills && cp -r skills-src/plugins/firefox-devtools-mcp/skills/screenshot .github/skills/screenshot && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "screenshot" agent skill from https://github.com/mozilla/firefox-devtools-mcp/tree/main/plugins/firefox-devtools-mcp/skills/screenshot into .github/skills/screenshot/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "screenshot", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add mozilla/firefox-devtools-mcp --skill screenshot -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install mozilla/firefox-devtools-mcp screenshot --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mozilla/firefox-devtools-mcp.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/plugins/firefox-devtools-mcp/skills/screenshot .opencode/skills/screenshot && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "screenshot" agent skill from https://github.com/mozilla/firefox-devtools-mcp/tree/main/plugins/firefox-devtools-mcp/skills/screenshot into .opencode/skills/screenshot/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "screenshot", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
screenshotTake a screenshot of a URL or the current page. An agent skill from mozilla/firefox-devtools-mcp.
Screenshot is an agent skill from mozilla/firefox-devtools-mcp. Take a screenshot of a URL or the current page
Its SKILL.md is about 320 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
It works with Model Context Protocol. The repository describes itself as: Model Context Protocol server for Firefox DevTools - enables AI assistants to inspect and control Firefox browser through WebDriver BiDi.
2 steps, taken from the first numbered list in SKILL.md.
Read from SKILL.md and the folder at commit 5c69888. It shows what the files ask for, not the result of running them.
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Screenshot loads about 318 tokens when it runs. Until then it costs about 14 tokens; SKILL.md has 127 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
Its licence (Custom licence) doesn't allow us to republish the file, so here is its outline and opening line. It has 127 words (~318 tokens).
“Captures a screenshot of a URL or the current page and shows it to the user.”
Just SKILL.md in plugins/firefox-devtools-mcp/skills/screenshot of mozilla/firefox-devtools-mcp.
Open the folder on GitHubat commit 5c69888
Screenshot next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Screenshot this skillmozilla/firefox-devtools-mcp | 468 | — | ~318 | Automated safety check: Pass | Custom licence | |
| MCP Server Builderanthropics/skills | 180k | 62 repos | ~2.3k | Automated safety check: Pass | Apache-2.0 | |
| MCP Server BuildershareAI-lab/learn-claude-code | 78k | 5 repos | ~1.2k | Automated safety check: Pass | MIT | |
| MCP Integration for Pluginsanthropics/claude-plugins-official | 37k | 11 repos | ~3.1k | Automated safety check: Pass | Apache-2.0 | |
| Figma use_figma Plugin API Ruleswarpdotdev/warp | 65k | 4 repos | ~4.4k | Automated safety check: Pass | AGPL-3.0 | |
| Stitch to Remotion Walkthrough Videosgoogle-labs-code/stitch-skills | 8.4k | 6 repos | ~3.2k | Automated safety check: Notes | Apache-2.0 |
anthropics/skills
Guides the design and implementation of Model Context Protocol servers in TypeScript or Python, from tool naming and error messages to evaluation.
shareAI-lab/learn-claude-code
Walks through building MCP servers in Python or TypeScript that expose tools, resources and prompts to Claude, with templates, registration and testing.
anthropics/claude-plugins-official
Explains how to bundle Model Context Protocol servers in a Claude Code plugin, covering config files, stdio, SSE, HTTP and WebSocket server types, and authentication.
warpdotdev/warp
Required groundwork before any use_figma call: the rules and reference files for running JavaScript in a Figma file through the Plugin API without common failures.
google-labs-code/stitch-skills
Builds walkthrough videos from Stitch design projects using Remotion, with transitions, zoom effects and text overlays on each screen.
coollabsio/coolify
A skill your agent uses for Laravel MCP development. An agent skill from coollabsio/coolify.
mozilla/firefox-devtools-mcp
Find and fix why a website is slow by capturing and analyzing a Firefox performance profile, or by analyzing a profile the user already has (a saved file or a profiler.firefox.com share link).
mozilla/firefox-devtools-mcp
This skill should be used when the user asks about browser automation, testing web pages, extracting content, filling forms, taking screenshots, or monitoring console/network activity.
mozilla/firefox-devtools-mcp
Diagnose Firefox DevTools MCP setup issues. An agent skill from mozilla/firefox-devtools-mcp.
mozilla/firefox-devtools-mcp
Show console errors and failed network requests. An agent skill from mozilla/firefox-devtools-mcp.
mozilla/firefox-devtools-mcp
Navigate Firefox to a URL and take a DOM snapshot for interaction
Works with
Take a screenshot of a URL or the current page. An agent skill from mozilla/firefox-devtools-mcp. Screenshot is an agent skill from mozilla/firefox-devtools-mcp.
Run `npx skills add mozilla/firefox-devtools-mcp --skill screenshot -a claude-code`. Or copy the skill folder (plugins/firefox-devtools-mcp/skills/screenshot in mozilla/firefox-devtools-mcp) into .claude/skills/screenshot in your project. Claude Code loads it when a task matches its description.
Run `npx skills add mozilla/firefox-devtools-mcp --skill screenshot -a codex`. Or copy the skill folder (plugins/firefox-devtools-mcp/skills/screenshot in mozilla/firefox-devtools-mcp) into .agents/skills/screenshot in your project. Codex loads it when a task matches its description.
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add mozilla/firefox-devtools-mcp --skill screenshot -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/screenshot, .gemini/skills/screenshot, .github/skills/screenshot and .opencode/skills/screenshot in your project.
SKILL.md names no scripts, command-line tools or credentials: Screenshot is instructions for the agent only.
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
Screenshot has a licence file (the repository's licence) that doesn't match a standard licence. Read it on GitHub before reusing the skill.
About 318 tokens (SKILL.md is roughly 1.3k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
Skills that share tags, products or a category with Screenshot: MCP Server Builder (anthropics/skills, 180k stars), MCP Server Builder (shareAI-lab/learn-claude-code, 78k stars), MCP Integration for Plugins (anthropics/claude-plugins-official, 37k stars) and Figma use_figma Plugin API Rules (warpdotdev/warp, 65k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
mozilla (a GitHub organization) maintains it in mozilla/firefox-devtools-mcp, which has 468 GitHub stars. The repository holds 6 skills in this directory. The repository was last updated on October 6, 2026.
Source: mozilla/firefox-devtools-mcp on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.