Saved-call compatibility
Find the exact recorded inputs and outputs that no longer satisfy a contract.
MCP release checks
Know what a tool
update changes.
Check saved calls against a new tool inventory. See exact failures before updating your integration.
Check a release
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Example data. This fictional inventory contains a breaking update.
Your release report will appear here.
Load the example, or use two complete tools/list inventories and your recorded cases.
A schema change is only part of the story.
A new output can satisfy its own schema and still break a consumer written for the previous version. Callstead checks the supplied output against both contracts and the expectations you record.
Advertised behavior changes
Review changes to read-only, destructive, retry and external-access hints.
Evidence you can keep
Export a portable report and keep the exact findings with your release review.