feat: mcp prompts as slash commands (alternative) (#5767)

Co-authored-by: Aiden Cline <63023139+rekram1-node@users.noreply.github.com>
Co-authored-by: Aiden Cline <aidenpcline@gmail.com>

packages/opencode/src/command/index.ts

@@ -6,6 +6,7 @@ import { Instance } from "../project/instance"
 import { Identifier } from "../id/id"
 import PROMPT_INITIALIZE from "./template/initialize.txt"
 import PROMPT_REVIEW from "./template/review.txt"
+import { MCP } from "../mcp"
 
 export namespace Command {
   export const Event = {
@@ -26,13 +27,28 @@ export namespace Command {
       description: z.string().optional(),
       agent: z.string().optional(),
       model: z.string().optional(),
-      template: z.string(),
+      // workaround for zod not supporting async functions natively so we use getters
+      // https://zod.dev/v4/changelog?id=zfunction
+      template: z.promise(z.string()).or(z.string()),
       subtask: z.boolean().optional(),
+      hints: z.array(z.string()),
     })
     .meta({
       ref: "Command",
     })
-  export type Info = z.infer<typeof Info>
+
+  // for some reason zod is inferring `string` for z.promise(z.string()).or(z.string()) so we have to manually override it
+  export type Info = Omit<z.infer<typeof Info>, "template"> & { template: Promise<string> | string }
+
+  export function hints(template: string): string[] {
+    const result: string[] = []
+    const numbered = template.match(/\$\d+/g)
+    if (numbered) {
+      for (const match of [...new Set(numbered)].sort()) result.push(match)
+    }
+    if (template.includes("$ARGUMENTS")) result.push("$ARGUMENTS")
+    return result
+  }
 
   export const Default = {
     INIT: "init",
@@ -46,13 +62,19 @@ export namespace Command {
       [Default.INIT]: {
         name: Default.INIT,
         description: "create/update AGENTS.md",
-        template: PROMPT_INITIALIZE.replace("${path}", Instance.worktree),
+        get template() {
+          return PROMPT_INITIALIZE.replace("${path}", Instance.worktree)
+        },
+        hints: hints(PROMPT_INITIALIZE),
       },
       [Default.REVIEW]: {
         name: Default.REVIEW,
         description: "review changes [commit|branch|pr], defaults to uncommitted",
-        template: PROMPT_REVIEW.replace("${path}", Instance.worktree),
+        get template() {
+          return PROMPT_REVIEW.replace("${path}", Instance.worktree)
+        },
         subtask: true,
+        hints: hints(PROMPT_REVIEW),
       },
     }
 
@@ -62,8 +84,36 @@ export namespace Command {
         agent: command.agent,
         model: command.model,
         description: command.description,
-        template: command.template,
+        get template() {
+          return command.template
+        },
         subtask: command.subtask,
+        hints: hints(command.template),
+      }
+    }
+    for (const [name, prompt] of Object.entries(await MCP.prompts())) {
+      result[name] = {
+        name,
+        description: prompt.description,
+        get template() {
+          // since a getter can't be async we need to manually return a promise here
+          return new Promise<string>(async (resolve, reject) => {
+            const template = await MCP.getPrompt(
+              prompt.client,
+              prompt.name,
+              prompt.arguments
+                ? // substitute each argument with $1, $2, etc.
+                  Object.fromEntries(prompt.arguments?.map((argument, i) => [argument.name, `$${i + 1}`]))
+                : {},
+            ).catch(reject)
+            resolve(
+              template?.messages
+                .map((message) => (message.content.type === "text" ? message.content.text : ""))
+                .join("\n") || "",
+            )
+          })
+        },
+        hints: prompt.arguments?.map((_, i) => `$${i + 1}`) ?? [],
       }
     }