[Makisuo]

Tweets still showed "Tweet not found" after #386.

Cause: Effect.provide(FetchHttpClient.layer) inside a command reuses the runtime's memoized FetchHttpClient.layer, which is the RPC client's, built with credentials: "include". The link-preview worker answers Access-Control-Allow-Origin: *, and browsers refuse that for a credentialed request. In prod the app's /tweet?id=… requests ended with status 0 in 13–27ms, while the same request without credentials returned 200.

Fix: the unfurl fetches (chat/unfurl.ts) and the emoji-data CDN fetch (emoji-picker/data.ts, same pattern) provide Layer.fresh(FetchHttpClient.layer).

Added unfurl-fetch.test.ts: the memoized layer sends include, the fresh one sends nothing.

🤖 Generated with Claude Code

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^{Need help on this PR? Tag @codesmith-bot with what you need.}

[maple-review-bot]

Maple review

🟢 Confidence 8/10 · likely safe to merge. The Layer.fresh swap is correct against Effect's layerMergedContext; only the test does not cover the app code it fixes.
_{1 warning −1 · tests partial −1 · risk medium}

Makes the link-preview and emoji-CDN fetches build their own FetchHttpClient layer, so they stop inheriting the RPC client's RequestInit and authenticatedFetch. Correct in mechanism; the added test does not pin it.

• getJson provides Layer.fresh(FetchHttpClient.layer) instead of the shared layer
• fetchEmojiData does the same for the jsdelivr CDN fetches

Findings

🟠 Warning · F1 · Reverting Layer.fresh here and in data.ts leaves unfurl-fetch.test.ts green

tests · apps/web-foldkit/src/chat/unfurl.ts:333

The new test builds its own Rpc layer and never runs getJson or fetchEmojiData, so it pins Effect's memoization behaviour, not this fix: putting Effect.provide(FetchHttpClient.layer) back at unfurl.ts:333 and emoji-picker/data.ts:193 keeps it passing while tweets go back to "Tweet not found".

Export `getJson` and run it in the test with the fake `Fetch` plus the RPC resources in context, asserting the recorded `init.credentials` is undefined.

🤖 Prompt to fix this finding with an AI agent

Findings from an automated review of commit 8e744e78ee4e072be4a527dfc5789d78af4ad086. Verify each one against the current code before changing anything, fix only those that still apply, and keep each fix to the lines it names.

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F1 · Warning · tests · apps/web-foldkit/src/chat/unfurl.ts:333
Reverting `Layer.fresh` here and in `data.ts` leaves `unfurl-fetch.test.ts` green
The new test builds its own `Rpc` layer and never runs `getJson` or `fetchEmojiData`, so it pins Effect's memoization behaviour, not this fix: putting `Effect.provide(FetchHttpClient.layer)` back at `unfurl.ts:333` and `emoji-picker/data.ts:193` keeps it passing while tweets go back to "Tweet not found".
Suggested fix: Export `getJson` and run it in the test with the fake `Fetch` plus the RPC resources in context, asserting the recorded `init.credentials` is undefined.

_{8e744e7 · What was checked, coverage and telemetry details are on the Maple / review check. Reply "won't fix" to dismiss a finding, or mention @maple-review-bot to ask about one.}

[coderabbitai]

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[maple-review-bot]

1 inline note from Maple's review. The score and summary are in the review comment above.

[maple-review-bot]

Warning

Reverting Layer.fresh here and in data.ts leaves unfurl-fetch.test.ts green

_{F1 · Warning · tests}

The new test builds its own Rpc layer and never runs getJson or fetchEmojiData, so it pins Effect's memoization behaviour, not this fix: putting Effect.provide(FetchHttpClient.layer) back at unfurl.ts:333 and emoji-picker/data.ts:193 keeps it passing while tweets go back to "Tweet not found".

Export `getJson` and run it in the test with the fake `Fetch` plus the RPC resources in context, asserting the recorded `init.credentials` is undefined.

🤖 Prompt to fix with an AI agent

In `apps/web-foldkit/src/chat/unfurl.ts:333`: Reverting `Layer.fresh` here and in `data.ts` leaves `unfurl-fetch.test.ts` green.

The new test builds its own `Rpc` layer and never runs `getJson` or `fetchEmojiData`, so it pins Effect's memoization behaviour, not this fix: putting `Effect.provide(FetchHttpClient.layer)` back at `unfurl.ts:333` and `emoji-picker/data.ts:193` keeps it passing while tweets go back to "Tweet not found".

Suggested fix: Export `getJson` and run it in the test with the fake `Fetch` plus the RPC resources in context, asserting the recorded `init.credentials` is undefined.

Verify the problem exists at that location before changing it, and keep the fix to those lines.

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	70.77%	22865 / 32307
🔵	Statements	70.18%	25860 / 36844
🔵	Functions	60.19%	8919 / 14817
🔵	Branches	58.94%	11181 / 18970

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
apps/web-foldkit/src/chat/unfurl.ts	84.52%	78.33%	64.51%	86.48%	82-83, 215-220, 234, 249, 308-311, 327-336, 344-348, 357-361
apps/web-foldkit/src/emoji-picker/data.ts	51.09%	33.33%	22.5%	54.23%	53, 57-59, 64-65, 67, 101-117, 121-129, 133-141, 147-188, 198-213, 218-223, 231-243

Generated in workflow #1998 for commit 8e744e7 by the Vitest Coverage Report Action