Tools

Guides the agent through writing or improving a skill: clarify intent, draft SKILL.md, run scored evals with and without the skill, then tune the description so it triggers accurately. Official Anthropic skill.

Controls your local Chrome over CDP to navigate, click, type, take screenshots and scrape data, reusing logged-in sessions. Official browser-use skill; install the browser-use CLI with uv first.

166 research skills maintained by K-Dense (formerly Claude Scientific Skills), spanning bioinformatics, cheminformatics, clinical research, materials and physics, including unified access to 78 public databases such as PubChem and UniProt. Works with Claude Code, Codex and Cursor.

Skills from security firm Trail of Bits: 40+ plugins for code auditing, CodeQL and Semgrep static analysis, differential review, smart-contract and cryptography audits, fuzzing and more. Also installable as a Claude Code or Codex plugin marketplace.

Reference for the Claude API and Anthropic SDK: model selection and pricing, streaming, tool use, prompt caching, Managed Agents and more, plus workflows for model migration and prompt audits. Official Anthropic skill.

Guides agents in building quality MCP servers: research the protocol and target API, design tools, implement with Python (FastMCP) or the TypeScript SDK, and write evaluation questions to test the result. Official Anthropic skill.

Creates, edits and analyzes Excel spreadsheets: formulas, formatting, charts and data cleaning, plus conversion between CSV, TSV and other tabular formats. The official Anthropic skill behind Claude's document features; source-available, not open source.

Unified database lookup skill from K-Dense's scientific collection: reproducibly queries about 80 public database APIs such as PubChem, UniProt, ChEMBL, ClinicalTrials.gov and FRED, returning traceable results with endpoints, parameters and count checks. Some need API keys.

Guides agents to the right statistical method for research data: t-tests, ANOVA, chi-square, regression and Bayesian analysis, checking assumptions, computing effect sizes and power, and reporting results in APA format. Python-based (pingouin, statsmodels); by K-Dense.

Teaches agents standard single-cell RNA-seq analysis with Scanpy: QC, normalization, PCA/UMAP, clustering, differential expression and plots, with ready-to-run pipeline scripts and guidance on converting Seurat and other R objects to h5ad. Needs Python 3.12+; by K-Dense.

Collection of 2,400+ installable SKILL.md skills across development, security, cloud and ops, AI, marketing and more, with the AAS Core local MCP and an installer that help agents search, pick skills and preview install plans. Formerly antigravity-awesome-skills.

EU GDPR compliance skill covering lawful bases, consent management, access and deletion requests, data retention and breach notification, with checklists and sample code so legal and engineering can review privacy together. No account or API key; have a lawyer check conclusions.

The 180+ skills bundled with the 90+ plugins in the wshobson/agents marketplace, covering development across many languages and frameworks, testing, ops, security, data and LLM apps. Install individually with npx skills or gh skill; skills only, without subagents or commands.

Official Anthropic skill for cleaning messy Excel exports: trims spaces, standardizes case and dates, converts text numbers, dedupes, and flags mixed types, garbled text and errors. Keeps originals via helper-column formulas and confirms each step. Works in Claude for Excel; local files need Python.

Official Anthropic finance skill that checks Excel for formula errors like #REF!, numbers hardcoded in formulas, sum ranges that miss rows and mixed units; on full models it also checks the balance sheet balances and cash ties. Lists issues and fixes and asks before changing anything.

When a user asks whether a skill exists for some task, searches the skills.sh ecosystem with the skills CLI, then recommends and installs a fit. Maintained by Vercel Labs and shipped in the skills CLI repo.

Community-maintained cybersecurity skill library: 800+ skills across 34 domains including threat hunting, incident forensics, penetration testing and cloud security, mapped to MITRE ATT&CK and NIST CSF. Not by Anthropic; offensive skills are for authorized testing only.

Anthropic's official data skill that guides agents to write, translate and optimize SQL across Snowflake, BigQuery, Databricks, PostgreSQL and other warehouse dialects, including CTEs, window functions and analytical aggregations.

Turns campaign or channel data into weekly, monthly or quarterly marketing reports: executive summary, key metrics and period-over-period trends, wins and misses, and next-period priorities. Connect analytics tools or just paste tables or key numbers. From Anthropic's knowledge-work-plugins.

Compliance skill from Anthropic's official operations plugin: maps controls, owners and evidence for SOC 2, ISO 27001, GDPR, HIPAA and PCI DSS, schedules audits, runs gap analyses, and outputs audit-readiness checklists and evidence collection plans. Have legal or compliance experts review.

Generates people analytics reports from employee data: headcount snapshots, voluntary and involuntary attrition, diversity metrics, spans of control and flight risk, with findings and recommendations for leadership. Needs an uploaded employee CSV or a connected HRIS. Official from Anthropic.

Manages BigQuery datasets, tables and jobs with the bq and gcloud CLIs, runs SQL queries and loads data, with references for client libraries, MCP and Terraform. Google's official skill; requires a Google Cloud project.

Google's official skill that queries account data through the Google Ads MCP server to diagnose conversion drops, falling leads and impression share lost to bids, budgets or ad rank. Needs a Google Ads account, API credentials (developer token and OAuth) and Python 3.12.

Google's official skill library, focused on Google Cloud: 100+ skills for gcloud, Cloud Run, GKE, BigQuery, IAM, monitoring and logging, and the Well-Architected Framework, plus Ads and Analytics.