What Is the Model Context Protocol?
One standard way for an AI app to reach tools and data.
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API engineering, from the spec out
Product updates, engineering notes, and guides for designing, debugging, testing, mocking, and serving MCP tools from one OpenAPI spec.
Browse the guidesRate Limiting an Upstream API Inside an MCP Tool
Protect the shared upstream behind every MCP tool.
Read articleMCP OAuth Token Rotation: How Refresh Tokens Stay Safe
Rotate refresh tokens so a leaked one expires fast.
Read articleMCP Resource Templates vs Tools: When to Use Each
Read data through resource templates, act through tools.
Read articleMCP Tool Versioning and Deprecated Tools
Version MCP tools by convention, then retire old names in stages.
Read articleTesting Bulk Endpoint Partial Failure
A bulk call is a set of per-item outcomes, not one pass or fail.
Read articleTesting Webhook Signature Verification
A signature is only useful if the bad branches are actually exercised.
Read articleTesting File Upload Size Boundaries
The file that matters is the one whose byte count sits exactly on the limit.
Read articleTesting Backwards-Compatible Additive Changes
A field that looks optional can still break a client that parses its responses strictly.
Read articleTesting Cache Invalidation Headers
A cache rule is only as good as the stale and revalidation cases.
Read articleTesting the Permission Matrix
A matrix that only proves the admin can do everything has not really been tested.
Read articleTesting Client Timeout Behavior
A client that gives up at the wrong millisecond either waits forever or drops a request that was about to succeed.
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