Field notes on AI-native SaaS.
How to ship MCP servers, embed in-product AI assistants, and monetize AI usage — written by the team building the platform.
- MCP education
isError is not an error: how an MCP tool fails and still looks successful
The MCP isError flag rides inside a successful JSON-RPC response, which is why hosts miss it. Three production bugs from our gateway: the failure a host has no name for, HTTP 200 with a GraphQL errors array, and the null result that isn't an error at all.
Sep 18, 2026 · 7 min - MCP education
GraphQL to MCP: introspection, nullability landmines, and lean selection sets
Turning a GraphQL API into MCP tools: query/mutation→tool mapping, why greedy selection sets explode on non-nullable fields, per-customer credential forwarding, and verb-accurate descriptions.
Jul 11, 2026 · 6 min - MCP education
Case study: AnnounceKit turned its GraphQL API into an 84-tool MCP in one afternoon
How AnnounceKit converted its GraphQL API into a hosted MCP server with 84 typed tools, per-customer authentication and usage analytics — live for Claude, Cursor and ChatGPT the same day.
Jul 11, 2026 · 7 min