Best Developer Tools APIs (2026)

Stack Overflow API includes 87 actions (questions, question, answers). Stack Overflow API The primary catalog return is items[] (questions: id, title, body, score, tags, owner→author, link), site, attribution; meta....

GitHub Developer Data includes 39 actions (user, user_repos, user_followers). GitHub Developer Data The primary catalog return is user{} — login, id, name, bio, company, blog, location, public_repos, followers, following, cre....

Developer Utilities API includes 21 actions (hash, uuid, encode). Developer Utilities API The primary catalog return is algo, hex, base64, base64url, length_bits, hmac (crc32/adler32: hex, decimal).

Generation API includes 21 actions (pdf_render, pdf_from_html, pdf_from_url). Generation API The primary catalog return is file{file_b64|download_token, filename, content_type=application/pdf, bytes, pages_hint, delive....

Product Hunt API scraper includes 13 actions (posts, post, reviews). Product Hunt API scraper The primary catalog return is posts[] (id, slug, name, tagline, upvotes, comments_count, daily/weekly/monthly_rank, topics, p....

Email Deliverability & DNS Health API includes 12 actions (check, spf, dmarc). Email Deliverability & DNS Health API The primary catalog return is domain, score{score,grade,breakdown}, spf{}, dkim{}, dmarc{}, mx{}, bimi{}, mta_sts{}, tls_rpt{....

Email Preflight API includes 7 actions (audit_html, css_support, spam_score). Email Preflight API The primary catalog return is html_validity{parse_ok,warnings[]}, size{bytes,gmail_clip_risk,limit}, accessibility{missing_al....

Package Registries API includes 7 actions (package, versions, version). Package Registries API The primary catalog return is package{} — name, latest version, description, license, homepage, repository, keywords, maintai....

Service Status & Incident API includes 7 actions (status, incidents, components). Service Status & Incident API The primary catalog return is vendor, name, indicator, is_operational, description, raw_indicator, active_incident_count, upd....

Vulnerability & Dependency Intelligence API includes 7 actions (package_vulns, vuln_detail, advisory_search). Vulnerability & Dependency Intelligence API The primary catalog return is package, ecosystem, version, vuln_count, severity_summary{by_severity:{critical,high,moderate,l....

Web Archive API includes 7 actions (snapshots, available, history). Web Archive API The primary catalog return is snapshots[] (timestamp, datetime, original, mimetype, statuscode, digest, length, snapshot_url)....

Domain Risk API includes 6 actions (assess, age, parked). Domain Risk API The primary catalog return is domain, registered, risk_score (0-100), risk_level (low|medium|elevated|high), reasons[] (plain....

MCP Server & Agent-Skill Registry API includes 6 actions (search, server_detail, skill_detail). MCP Server & Agent-Skill Registry API The primary catalog return is { results: [{id,name,title,type,description,github_url,license,version,transport[],status,updat....

Change-Detect API includes 5 actions (snapshot, diff, monitor_check). Change-Detect API The primary catalog return is content_hash, structural_hash, text_hash, title, meta_description, main_content, normalized_tex....

Threat Intelligence API includes 5 actions (url_check, domain_reputation, ip_reputation). Threat Intelligence API The primary catalog return is target, type, malicious (bool), verdict (clean|suspicious|malicious), score (0-100), sources[]....

Web Extract API includes 5 actions (scrape, map, crawl). Web Extract API The primary catalog return is final_url, title, metadata{canonical,lang,site_name,author,published_at,og,...}, extraction{met....

Package & Dependency Trust API includes 4 actions (package_trust, repo_trust, lockfile_scan). Package & Dependency Trust API The primary catalog return is package{name,ecosystem,version,description,homepage}, metadata{license{value,spdx,tier,risk_not....

Passive OSINT & Recon API includes 4 actions (subdomains, domain, ip). Passive OSINT & Recon API The primary catalog return is domain, count, subdomains[] (sorted unique), source_matrix{host:[sources]}, sources{per-source....