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{"id":"napkin-ai-api","name":"Napkin AI API","homepage":"https://www.napkin.ai","docs":"https://api.napkin.ai/","auth":"api_key","auth_hint":"Authorization: Bearer <api_token>","mcp":{"type":"none","url":null,"maintainer":"none","source_url":"https://api.napkin.ai/faq","checked_at":"2026-09-24","domain_verified":null,"kind":"none","config":null},"free_tier":"included on every plan; any account can create a token and call the API, limited by credits","sdk":[],"openapi":null,"llms_txt":null,"desc_en":"Generate diagrams, flowcharts, mind maps, and charts from text via REST API, exporting to SVG, PNG, or PPT.","notes":"Credit-based usage; requests fail with a no_credits error once a team's credits are exhausted.","verified":"2026-09-24","free_plan":{"kind":"free_tier","quota":"500 AI credits per week (shared with the app)","watermark":true,"source_url":"https://www.napkin.ai/pricing","checked_at":"2026-09-24"},"auth_scheme":{"type":"http","scheme":"bearer","format":"Authorization: Bearer <API_TOKEN>","source_url":"https://api.napkin.ai/api/create-visual-request","checked_at":"2026-09-24"},"base_url":"https://api.napkin.ai/v1","rate_limits":{"summary":"POST /v1/visual throttled per second/minute/hour/day by plan; X-RateLimit-* and Retry-After headers","source_url":"https://api.napkin.ai/","checked_at":"2026-09-24"},"async_jobs":{"value":true,"how":"POST /v1/visual returns request id; poll GET /v1/visual/{id}/status; file URLs expire after 30 min","source_url":"https://api.napkin.ai/"},"operations":["diagram-rendering"],"no_auth":false,"call":{"operation":"create a visual from text","method":"POST","url":"https://api.napkin.ai/v1/visual","example":"curl -X POST https://api.napkin.ai/v1/visual -H \"Authorization: Bearer $NAPKIN_API_TOKEN\" -H \"Content-Type: application/json\" -d '{\"format\":\"svg\",\"content\":\"Napkin API\"}'","response_fields":["id","status"],"async":"poll GET https://api.napkin.ai/v1/visual/{request-id}/status until status is completed, then download each generated_files URL with the same Authorization header (URLs expire after 30 min)","source_url":"https://api.napkin.ai/api/create-visual-request","checked_at":"2026-09-24"},"has_free_tier":true,"has_trial":false,"no_card":false,"stale":false,"link_check":{"checked_at":"2026-09-24","docs":"ok"},"uptime":{"window_days":30,"api":{"url":"https://api.napkin.ai/v1","probes":1,"up":1,"median_ms":463,"last":{"at":"2026-09-24T18:26Z","up":true,"detail":404}}}},
{"id":"plantuml-server-api","name":"PlantUML Server API","homepage":"https://plantuml.com","docs":"https://plantuml.com/server","auth":"none","auth_hint":"","mcp":{"type":"none","url":null,"maintainer":"vendor","repo":"https://github.com/plantuml/plantuml-mcp","tools":["plantuml_version"],"covers_full_api":false,"source_url":"https://github.com/plantuml/plantuml-mcp","checked_at":"2026-09-24","domain_verified":null,"kind":"official","config":null},"free_tier":"free, no key; public hosted server at plantuml.com/plantuml","sdk":[],"openapi":null,"llms_txt":null,"desc_en":"Render UML and architecture-as-code diagrams to PNG/SVG/ASCII via a free public HTTP GET API using encoded diagram text.","notes":"Extremely widely used for UML/C4/architecture-as-code; no signup; self-hostable via plantuml.war for privacy or rate-limit control. The official plantuml/plantuml-mcp is an MVP exposing only plantuml_version (no rendering yet).","verified":"2026-09-24","free_plan":{"kind":"no_key","requires_card":false,"source_url":"https://plantuml.com/server","checked_at":"2026-09-24"},"auth_scheme":{"type":"none","format":"GET https://www.plantuml.com/plantuml/{png|svg|txt}/<ENCODED_SOURCE>","source_url":"https://plantuml.com/server","checked_at":"2026-09-24"},"base_url":"https://www.plantuml.com/plantuml","async_jobs":{"value":false,"how":"synchronous: image returned in the HTTP response","source_url":"https://plantuml.com/server"},"operations":["diagram-rendering"],"no_auth":true,"call":{"operation":"render a diagram to PNG","method":"GET","url":"https://www.plantuml.com/plantuml/png/{ENCODED_SOURCE}","example":"curl -o diagram.png https://www.plantuml.com/plantuml/png/SyfFKj2rKt3CoKnELR1Io4ZDoSa70000","response_fields":["body: PNG image bytes (use /svg/ for SVG, /txt/ for ASCII)","Content-Type"],"async":null,"source_url":"https://plantuml.com/server","checked_at":"2026-09-24"},"has_free_tier":true,"has_trial":false,"no_card":true,"stale":false,"link_check":{"checked_at":"2026-09-24","docs":"ok"},"uptime":{"window_days":30,"api":{"url":"https://www.plantuml.com/plantuml","probes":1,"up":1,"median_ms":799,"last":{"at":"2026-09-24T18:26Z","up":true,"detail":200}}}},
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]}