docs: add Instantly data warehouse source

[Gilbert09]

Changes

Adds the user-facing doc for the new Instantly data warehouse source, implemented in PostHog/posthog#72659.

Why: the source ships with docsUrl pointing at /docs/cdp/sources/instantly, so the doc needs to exist to avoid a 404 from the source setup UI.

Follows the canonical source-doc template: alpha callout, prerequisites (Growth plan, scoped API keys), shared setup/sync-mode snippets, <SourceParameters /> and <SourceTables /> (rendered from the source's static table catalog and canonical descriptions), a webhooks section for the optional real-time webhook_events stream, and troubleshooting. audit_source_docs passes against this checkout.

This should merge around the same time as the source PR (the sourceId: Instantly config it renders from goes live with that deploy).

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Created with PostHog Code

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Deploy preview

Status	Details	Updated (UTC)
🟢 Ready	View preview	Jul 21, 2026 03:26PM

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Vale prose linter → found 0 errors, 2 warnings, 0 suggestions in your markdown

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contents/docs/cdp/sources/instantly.md — 0 errors, 2 warnings, 0 suggestions

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48:32	warning	'Hypergrowth' is a possible misspelling.	PostHogBase.Spelling
61:122	warning	'Hypergrowth' is a possible misspelling.	PostHogBase.Spelling

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Bundle report

Total JS (gzip)

6.72 MiB (no change)

Eager graph (modules shipped in each entrypoint's initial chunks)

Entrypoint	Eager size	Budget	Modules
✅ app	16.09 MiB (no change)	report-only	1970

Largest modules in the app closure

Module	Size
./src/data/mcp-tools.json	866.0 KiB
css ./node_modules/.pnpm/css-loader@5.2.7_webpack@5.101.3/node_modules/css-loader/dist/cjs.js??ruleSet[1].rules[8].oneOf[1].use[1]!./node_modules/.pnpm/postcss-loader@4.3.0_postcss@8.5.6_webpack@5.101.3/node_modules/postcss-loader/dist/cjs.js??ruleSet[1].rules[8].oneOf[1].use[2]!./src/styles/global.css	743.0 KiB
./src/components/Stickers/Stickers.tsx	696.4 KiB
./node_modules/.pnpm/@radix-ui+react-icons@1.3.2_react@18.3.1/node_modules/@radix-ui/react-icons/dist/react-icons.esm.js	481.4 KiB
./node_modules/.pnpm/rehype-raw@7.0.0/node_modules/rehype-raw/lib/index.js + 29 modules	395.1 KiB
./node_modules/.pnpm/@posthog+icons@0.36.6_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/@posthog/icons/dist/posthog-icons.cjs.js	364.8 KiB
./src/hooks/useCustomers.tsx + 54 modules	355.1 KiB
./node_modules/.pnpm/@posthog+icons@0.36.6_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/@posthog/icons/dist/posthog-icons.es.js	354.8 KiB
./node_modules/.pnpm/react-markdown@8.0.7_@types+react@16.14.66_react@18.3.1/node_modules/react-markdown/lib/react-markdown.js + 88 modules	351.4 KiB
./node_modules/.pnpm/cloudinary-core@2.14.0_lodash@4.17.21/node_modules/cloudinary-core/cloudinary-core.js	281.9 KiB
./src/components/ProductComparisonTable/index.tsx + 120 modules	278.6 KiB
./src/components/SearchUI/index.tsx + 87 modules	271.9 KiB
./node_modules/.pnpm/d3@7.9.0/node_modules/d3/src/index.js + 208 modules	247.4 KiB
./src/components/Pricing/PricingSlider/Slider.tsx + 87 modules	239.9 KiB
./gatsby-browser.tsx + 43 modules	225.0 KiB

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Eager-graph budgets are report-only until a baseline is established. Sizes are gzip of public/**/*.js; eager size is webpack module source bytes for the modules actually shipped in the entrypoint's initial chunks (post-tree-shake).