init MCP server

MCP_SERVER_GUIDE.md

@@ -0,0 +1,149 @@
+# MCP Server for Code Snippets Database
+
+## Overview
+
+Building an MCP (Model Context Protocol) server to create a CRUD interface for managing code snippets. The goal is to enable Claude to save commands/code directly to your snippets database through natural conversation.
+
+## What is an MCP Server?
+
+An MCP server is an executable that communicates with clients (like Claude IDE) by exchanging JSON messages. At its core:
+
+1. **Reads JSON** from stdin (messages from the client)
+2. **Writes JSON** to stdout (responses back)
+3. Implements the MCP protocol using JSON-RPC 2.0
+
+Official docs: https://modelcontextprotocol.io/docs/concepts/architecture
+
+## Transport Mechanisms
+
+MCP servers support three transport types (choose one):
+
+### 1. **Stdio** (Most Common)
+- Server runs as a subprocess
+- Client spawns the executable and pipes JSON over stdin/stdout
+- Best for: local integrations, Claude IDE plugins
+
+### 2. **HTTP**
+- Server runs as an HTTP service (listens on a port)
+- Client sends JSON over HTTP requests
+- Best for: remote servers, shared services, multiple clients
+
+### 3. **SSE** (Server-Sent Events)
+- Used alongside HTTP for server→client streaming
+- Less common
+
+For this project, **stdio is the natural choice** — simple implementation and works seamlessly with Claude IDE.
+
+## Protocol Flow
+
+### 1. Initialize Handshake
+
+**Client → Server:**
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "initialize",
+  "params": {
+    "protocolVersion": "2024-11-05",
+    "capabilities": {},
+    "clientInfo": {
+      "name": "claude-code",
+      "version": "1.0.0"
+    }
+  }
+}
+```
+
+**Server → Client Response:**
+```json
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "result": {
+    "protocolVersion": "2024-11-05",
+    "capabilities": {
+      "tools": {
+        "listChanged": true
+      },
+      "resources": {
+        "listChanged": true
+      },
+      "prompts": {
+        "listChanged": true
+      }
+    },
+    "serverInfo": {
+      "name": "snippets-server",
+      "version": "1.0.0"
+    }
+  }
+}
+```
+
+Key points:
+- **JSON-RPC 2.0 format**: includes `jsonrpc`, `id`, and `method` fields
+- **Server declares capabilities**: tells client what it offers (tools, resources, prompts)
+- **Protocol version agreement**: both sides confirm compatibility
+- **Server info**: client learns about your server
+
+### 2. Subsequent Calls
+
+After initialization, the client can call methods like:
+- `tools/list` - get list of available tools
+- `tools/call` - execute a specific tool
+- `resources/list` - get available resources
+- `resources/read` - read a resource
+
+## Implementation Plan for Snippets Server
+
+Your MCP server should expose CRUD tools:
+
+1. **`create_snippet`** - Save a new snippet (language, description, code)
+2. **`list_snippets`** - List all snippets or filter by language/tag
+3. **`get_snippet`** - Retrieve a specific snippet by ID
+4. **`update_snippet`** - Modify an existing snippet
+5. **`delete_snippet`** - Remove a snippet
+6. **`search_snippets`** - Search snippets by content or description
+
+Each tool definition includes:
+- Name and description
+- Input schema (JSON Schema format)
+- Output schema
+
+## Getting Started
+
+1. Choose a language (Node.js/Bun, Python, Go, Rust recommended)
+2. Create a basic stdio-based server that:
+   - Reads from stdin
+   - Parses JSON-RPC messages
+   - Implements initialize handshake
+   - Implements tools/list and tools/call
+3. Connect to your snippets database/storage
+4. Test by running the server and sending JSON messages
+
+## Useful Resources
+
+- MCP Protocol Spec: https://modelcontextprotocol.io/
+- Official example servers: https://github.com/modelcontextprotocol/servers
+- JSON-RPC 2.0: https://www.jsonrpc.org/specification
+
+## Use Case Flow
+
+```
+User (Claude IDE):
+"Save this bash command to my snippets"
+    ↓
+Claude analyzes and calls:
+    tools/call with tool="create_snippet"
+    ↓
+MCP Server receives JSON-RPC request
+    ↓
+Server creates snippet in database
+    ↓
+Returns success response to Claude
+    ↓
+User sees confirmation and snippet is saved
+```
+
+This creates a seamless workflow where your snippet database grows through natural conversation!

README.md

@@ -12,14 +12,14 @@ Interactive elements are powered by [Gum](https://github.com/charmbracelet/gum).
 To run commands:
 
 ```shell
-$ bb -m cli-cms.main create
+$ bb -m cli.main create
 ```
 
 Or to play around and call individual functions using the REPL:
 
 ```shell
 $ rlwrap bb repl
-user=> (require '[cli-cms.create :as command])
+user=> (require '[cli.create :as command])
 user=> (def mock-snippet {:title "mock snippet from repl" :slug "mock" :tags '("mock") :markdown "# This is a mock"})
 #'user/mock-snippet
 user=> (command/create-snippet mock-snippet)

snippets_cms.bb

@@ -1,7 +1,7 @@
 #!/usr/bin/env bb
 
 (ns snippets-cms
-  (:require [cli-cms.main]))
+  (:require [cli.main]))
 
 (when (= *file* (System/getProperty "babashka.file"))
-  (apply cli-cms.main/-main *command-line-args*))
+  (apply cli.main/-main *command-line-args*))

snippets_mcp.bb

@@ -0,0 +1,7 @@
+#!/usr/bin/env bb
+
+(ns snippets-mcp
+  (:require [cli.mcp]))
+
+(when (= *file* (System/getProperty "babashka.file"))
+  (apply cli.mcp/-main *command-line-args*))

src/cli/config.clj

@@ -1,4 +1,4 @@
-(ns cli-cms.config
+(ns cli.config
   (:require
    [babashka.fs :as fs]
    [clojure.string :as str]))

src/cli/create.clj

@@ -1,16 +1,16 @@
-(ns cli-cms.create
+(ns cli.create
   (:require
    [com.travisshears.gum-utils :as utils]
    [clojure.string :as str]
-   [cli-cms.config :refer [config]]
+   [cli.config :refer [config]]
    [babashka.http-client :as http]
    [cheshire.core :as json]
    [babashka.process :refer [shell]]))
 
 (defn create-snippet [{:keys [title slug markdown tags]}]
   (http/post (str (:backend-host config) "/api/snippet")
-    {:headers {:content-type "application/json"}
-     :body (json/encode {:title title :slug slug :markdown markdown :tags tags})}))
+             {:headers {:content-type "application/json"}
+              :body (json/encode {:title title :slug slug :markdown markdown :tags tags})}))
 
 (defn run []
   (let [title (utils/prompt-for "title")

src/cli/delete.clj

@@ -1,7 +1,7 @@
-(ns cli-cms.delete
+(ns cli.delete
   (:require
    [com.travisshears.gum-utils :as utils]
-   [cli-cms.config :refer [config]]
+   [cli.config :refer [config]]
    [clojure.pprint :refer [pprint]]
    [babashka.http-client :as http]
    [cheshire.core :as json]))

src/cli/edit.clj

@@ -1,9 +1,9 @@
-(ns cli-cms.edit
+(ns cli.edit
   (:require
    [babashka.http-client :as http]
    [clojure.pprint :refer [pprint]]
-   [cli-cms.config :refer [config]]
-   [cli-cms.view :as view]
+   [cli.config :refer [config]]
+   [cli.view :as view]
    [cheshire.core :as json]
    [com.travisshears.gum-utils :as utils]))
 

src/cli/main.clj

@@ -1,10 +1,10 @@
-(ns cli-cms.main
+(ns cli.main
   (:require
-   [cli-cms.create :as create]
-   [cli-cms.edit :as edit]
-   [cli-cms.delete :as delete]
+   [cli.create :as create]
+   [cli.edit :as edit]
+   [cli.delete :as delete]
    [com.travisshears.gum-utils :as utils]
-   [cli-cms.view :as view]))
+   [cli.view :as view]))
 
 (defn color-test []
   (doseq [color (range 0 255)]

src/cli/mcp.clj

@@ -0,0 +1,76 @@
+(ns cli.mcp
+  (:require
+   [cli.view :as view]
+   [cheshire.core :as json]))
+
+;; Tool definitions
+(def available-tools
+  [{:name "list_snippets"
+    :description "List all available code snippets"
+    :inputSchema {:type "object"
+                  :properties {}
+                  :required []}}])
+
+;; Tool implementations
+(defn list-snippets-impl []
+  (try
+    (let [snippets (view/fetch-snippets)]
+      {:success true
+       :snippets (map #(select-keys % [:id :title :slug :tags]) snippets)})
+    (catch Exception e
+      {:success false
+       :error (.getMessage e)})))
+
+;; Handle tools/list request
+(defn handle-tools-list [id]
+  {:jsonrpc "2.0"
+   :id id
+   :result {:tools available-tools}})
+
+;; Handle tools/call request
+(defn handle-tools-call [id tool-name tool-input]
+  {:jsonrpc "2.0"
+   :id id
+   :result (case tool-name
+             "list_snippets" (list-snippets-impl)
+             {:error (str "Unknown tool: " tool-name)})})
+
+;; Handle initialize request
+(defn handle-initialize [id]
+  {:jsonrpc "2.0"
+   :id id
+   :result {:protocolVersion "2024-11-05"
+            :capabilities {:tools {:listChanged true}
+                           :resources {:listChanged true}
+                           :prompts {:listChanged true}}
+            :serverInfo {:name "snippets-server"
+                         :version "1.0.0"}}})
+
+;; Main request dispatcher
+(defn handle-request [request]
+  (let [method (:method request)
+        id (:id request)
+        params (:params request)]
+    (case method
+      "initialize" (handle-initialize id)
+      "tools/list" (handle-tools-list id)
+      "tools/call" (handle-tools-call id (:name params) (:arguments params))
+      {:jsonrpc "2.0"
+       :id id
+       :error {:code -32601
+               :message (str "Method not found: " method)}})))
+
+(defn -main [& args]
+  ;; Read JSON-RPC requests from stdin and process them
+  (loop []
+    (let [line (try (read-line) (catch Exception _))]
+      (when line
+        (try
+          (let [request (json/parse-string line true)
+                response (handle-request request)]
+            (println (json/encode response)))
+          (catch Exception e
+            (println (json/encode {:jsonrpc "2.0"
+                                   :error {:code -32700
+                                           :message "Parse error"}}))))
+        (recur)))))

src/cli/view.clj

@@ -1,8 +1,8 @@
-(ns cli-cms.view
+(ns cli.view
   (:require
    [babashka.http-client :as http]
    [clojure.pprint :refer [pprint]]
-   [cli-cms.config :refer [config]]
+   [cli.config :refer [config]]
    [cheshire.core :as json]
    [clojure.string :as str]
    [com.travisshears.gum-utils :as utils]))