For teams that call other people's APIs
Stripe renames a value. GitHub answers 200 instead of 204. SHAPI recognizes calls to GitHub, Stripe, Slack, OpenAI and 31 more APIs, finds the exact lines a change breaks, and where a fix recipe exists, sends a pull request that fixes them with a test that proves it.
Free for public repositories and one private repository. Free for everyone during early access.
13const res = await fetch(`…/dispatches`, {14 method: "POST",21});22if (res.status !== 204) {if (![200, 204].includes(res.status)) {23 throw new Error(`deploy dispatch failed with ${res.status}`);24}
Watching GitHub for changes to the endpoints this code calls.
GitHub changed. workflow_dispatch now answers 200 with a body, not 204.
Line 22 breaks. It only accepts 204, so every successful deploy now throws.
Fixed. A contract test failed before the fix and passes after it. Pull request opened.
The problem
They keep passing while the provider changes a status code, renames a field or adds a new value.
A version is retired on a date announced months ago, in a post nobody on your team read.
From an error report, a failed payment or an angry customer, not from your own checks.
How it works
Install the GitHub App. Each push to your default branch is scanned for calls to third-party APIs, through HTTP clients or official SDKs.
Each call is checked against reviewed API changes and deadlines: version sunsets, renamed fields, new status codes. Code that breaks is told apart from code that is fine.
For each affected TypeScript or JavaScript call with a fix recipe, SHAPI writes a contract test, confirms it fails, applies the fix, and opens a pull request only once the test passes.
Canaries probe providers every hour and announced changes are researched from changelogs, so the next change reaches you as a pull request or an alert, not an incident.
Coverage
A real break
In December 2025, GitHub's workflow dispatch endpoint started answering 200 OK with a body instead of 204 No Content. The docs still said 204. Code that required exactly 204 treated every successful deploy as a failure.
SHAPI finds each place your code checks for 204, proves the break with a test, and opens the fix.
src/deploy.ts+1 −1@@ -19,7 +19,7 @@- if (res.status !== 204) {+ if (![200, 204].includes(res.status)) { throw new Error(`deploy dispatch failed with ${res.status}`);
The fix SHAPI opened on its demo project: shapi-demo pull request #2.
Security
Sign-in reads who you are and which installations you can open, then drops the GitHub token. Sessions are stored only as a hash.
Every change arrives as a pull request on its own branch. You review and merge; SHAPI never writes to your default branch.
Fixes and their tests run in an isolated sandbox. Dependencies install from the package registry, then the network is cut.
Fixes come from deterministic recipes (11 of the 54 reviewed changes have one today). Claude is used only when you turn it on, and its change is kept only if the test passes.
Pricing
For open source and trying SHAPI on real code.
For companies whose product runs on other people's APIs.
Install in a minute. SHAPI scans your repositories right away, then on every push.