Save Post or Comment

Instructions

Implementation Reference

• src/tools/save.ts:16-53 (registration)

  The tool 'save_item' is registered via server.registerTool() with name 'save_item', including schema and handler in one call.

  export function register(server: McpServer, client: RedditClient): void {
    server.registerTool(
      "save_item",
      {
        title: "Save Post or Comment",
        description: "Save a Reddit post or comment to your saved items list.",
        inputSchema: z.object({
          url: z.string().describe("Full Reddit URL of the post or comment to save"),
        }),
      },
      async ({ url }) => {
        try {
          const thingId = extractThingId(url);
          if (!thingId) {
            return {
              content: [{ type: "text" as const, text: "Could not extract ID from URL." }],
              isError: true,
            };
          }
          await client.post("/api/save", { id: thingId });
          return {
            content: [
              {
                type: "text" as const,
                text: JSON.stringify({ success: true, id: thingId, saved: true }, null, 2),
              },
            ],
          };
        } catch (error) {
          return {
            content: [
              { type: "text" as const, text: `Error saving: ${error instanceof Error ? error.message : String(error)}` },
            ],
            isError: true,
          };
        }
      }
    );

• src/tools/save.ts:26-52 (handler)

  The handler function for 'save_item' that extracts a Reddit thing ID from a URL and calls client.post('/api/save', {id}) to save the item.

  async ({ url }) => {
    try {
      const thingId = extractThingId(url);
      if (!thingId) {
        return {
          content: [{ type: "text" as const, text: "Could not extract ID from URL." }],
          isError: true,
        };
      }
      await client.post("/api/save", { id: thingId });
      return {
        content: [
          {
            type: "text" as const,
            text: JSON.stringify({ success: true, id: thingId, saved: true }, null, 2),
          },
        ],
      };
    } catch (error) {
      return {
        content: [
          { type: "text" as const, text: `Error saving: ${error instanceof Error ? error.message : String(error)}` },
        ],
        isError: true,
      };
    }
  }

• src/tools/save.ts:22-24 (schema)

  Input schema for 'save_item' defines a single required string parameter 'url' (the full Reddit URL of the post or comment to save).

  inputSchema: z.object({
    url: z.string().describe("Full Reddit URL of the post or comment to save"),
  }),

• src/tools/save.ts:6-14 (helper)

  Helper function extractThingId() that parses a Reddit URL to extract the thing ID (t1_ for comments, t3_ for posts) used in the save API call.

  function extractThingId(url: string): string | null {
    const commentMatch = url.match(
      /\/comments\/[a-z0-9]+\/[^/]*\/([a-z0-9]+)/i
    );
    if (commentMatch) return `t1_${commentMatch[1]}`;
    const postMatch = url.match(/\/comments\/([a-z0-9]+)/i);
    if (postMatch) return `t3_${postMatch[1]}`;
    return null;
  }

• src/reddit/client.ts:159-185 (helper)

  The RedditClient.post() method called by the save_item handler. It sends a POST request to /api/save on the Reddit OAuth API with Bearer token authentication.

  async post(
    endpoint: string,
    body: Record<string, string>
  ): Promise<any> {
    await this.ensureToken();
    if (!this.session?.username) {
      throw new Error(
        "Write operations require authentication. Run the 'authorize' tool first to connect your Reddit account (one-time browser authorization)."
      );
    }
    const url = endpoint.startsWith("http")
      ? endpoint
      : `${OAUTH_BASE}${endpoint}`;
    const res = await fetch(url, {
      method: "POST",
      headers: {
        "Content-Type": "application/x-www-form-urlencoded",
        Authorization: `Bearer ${this.session!.accessToken}`,
        "User-Agent": this.userAgent,
      },
      body: new URLSearchParams({
        ...body,
        api_type: "json",
      }),
    });
    return res.json();
  }