T6-R3 in five minutes
A tool does something and returns a result.
A resource is data the server can show, like a note.
A prompt is a template the server offers.
Confirm the current spec's exact names before you code.
Mixing the three in one function makes the consent screen unclear.
Reading a note is a resource. Sending a message is a tool with a side effect. The consent copy should say which one the person is allowing.
Sources and go deeper
- Model Context Protocol specification, 2025-06-18 spec last checked 2026-10
- What is the Model Context Protocol (MCP)? spec last checked 2026-10
- Model Context Protocol organization on GitHub community last checked 2026-10
- Model Context Protocol — Wikipedia wikipedia last checked 2026-10