stories/ — the canonical reference. One self-verifying example per protocol feature, each with its own README. Start with stories/tools/; the stories README has the full table and how to run them.
snippets/ — short extracts that were embedded into the v1 README (now on the v1.x branch); superseded by docs_src/, which the docs and README embed today. Retained pending consolidation into stories/.
servers/everything-server/ — the conformance target for the cross-SDK conformance suite. Exercises every server capability in one process.
mcpserver/ — single-file v1-era examples retained for the migration guide; superseded by stories/ and slated for removal.
clients/ and the remaining servers/ directories (simple-*, sse-polling-demo, structured-output-lowlevel) — standalone v1-era projects retained pending consolidation into stories/ (the simple-auth pair is still linked from docs/run/authorization.md and docs/client/oauth-clients.md).

For real-world servers see the servers repository.