feat(opencode): add code-mode MCP adapter

packages/opencode/package.json

@@ -84,6 +84,7 @@
     "@octokit/graphql": "9.0.2",
     "@octokit/rest": "catalog:",
     "@openauthjs/openauth": "catalog:",
+    "@opencode-ai/codemode": "workspace:*",
     "@opencode-ai/llm": "workspace:*",
     "@opencode-ai/plugin": "workspace:*",
     "@opencode-ai/protocol": "workspace:*",

packages/opencode/src/permission/index.ts

@@ -213,6 +213,11 @@ export function disabled(tools: string[], ruleset: PermissionV1.Ruleset): Set<st
   )
 }
 
+export function visibleTools<T>(tools: Record<string, T>, ruleset: PermissionV1.Ruleset): Record<string, T> {
+  const hidden = disabled(Object.keys(tools), ruleset)
+  return Object.fromEntries(Object.entries(tools).filter(([name]) => !hidden.has(name)))
+}
+
 export const node = LayerNode.make({ service: Service, layer: layer, deps: [EventV2Bridge.node] })
 
 export * as Permission from "."

packages/opencode/src/tool/code-mode.ts

@@ -0,0 +1,322 @@
+import * as Tool from "./tool"
+import { CallToolResultSchema, type CallToolResult } from "@modelcontextprotocol/sdk/types.js"
+import { Cause, Effect, Schema } from "effect"
+import {
+  CodeMode,
+  Tool as SandboxTool,
+  toolError,
+  type ExecuteResult,
+  type JsonSchema,
+  type ToolDefinition,
+} from "@opencode-ai/codemode"
+import { MCP } from "@/mcp"
+import { McpCatalog } from "@/mcp/catalog"
+import { Agent } from "@/agent/agent"
+import { Session } from "@/session/session"
+import { Permission } from "@/permission"
+import { Plugin } from "@/plugin"
+
+export const CODE_MODE_TOOL = "execute"
+
+const DESCRIPTION = [
+  "Execute a JavaScript/TypeScript program that orchestrates the connected MCP tools inside a confined runtime.",
+  "The full usage guide and the catalog of available tools follow below.",
+].join("\n")
+
+export const Parameters = Schema.Struct({
+  code: Schema.String.annotate({
+    description: [
+      "JavaScript source to execute.",
+      "Inside CodeMode, `tools` contains only the MCP/CodeMode tools listed in this execute tool's description; top-level opencode tools like bash, read, or lsp are not available unless listed there.",
+      "Call available tools using the exact signatures shown in this execute tool's description, compose the results, and `return` the final value.",
+    ].join(" "),
+  }),
+})
+
+type CallEntry = { tool: string; status: "running" | "completed" | "error"; input?: Record<string, unknown> }
+
+type Metadata = {
+  toolCalls: CallEntry[]
+  error?: boolean
+}
+
+type Attachment = NonNullable<Tool.ExecuteResult["attachments"]>[number]
+
+type CatalogEntry = {
+  path: string
+  key: string
+  server: string
+  local: string
+  tool: MCP.McpTool
+}
+
+function groupByServer(mcpTools: Record<string, MCP.McpTool>, servers: readonly string[]): Map<string, CatalogEntry[]> {
+  const byLongest = [...servers].sort((a, b) => b.length - a.length)
+  const groups = new Map<string, CatalogEntry[]>()
+  for (const key of Object.keys(mcpTools).sort((a, b) => a.localeCompare(b))) {
+    const server =
+      byLongest.find((name) => key.startsWith(name + "_")) ?? (key.includes("_") ? key.slice(0, key.indexOf("_")) : key)
+    const local = server && key.startsWith(server + "_") ? key.slice(server.length + 1) : key
+    const entry: CatalogEntry = {
+      path: `${server}.${local}`,
+      key,
+      server,
+      local,
+      tool: mcpTools[key]!,
+    }
+    groups.set(server, [...(groups.get(server) ?? []), entry])
+  }
+  return groups
+}
+
+export function describeCatalog(mcpTools: Record<string, MCP.McpTool>, servers: readonly string[]): string {
+  return CodeMode.make({
+    tools: toolTree(
+      [...groupByServer(mcpTools, servers).values()].flat(),
+      () => () => Effect.fail(toolError("Tool preview is not executable.")),
+    ),
+  }).instructions()
+}
+
+const lastSegment = (uri: string) => {
+  const trimmed = uri.split(/[?#]/, 1)[0]!.replace(/\/+$/, "")
+  const segment = trimmed.slice(trimmed.lastIndexOf("/") + 1)
+  return segment.length > 0 ? segment : undefined
+}
+
+const dataUrl = (mime: string, base64: string) => `data:${mime};base64,${base64}`
+
+function projectMcpResult(result: CallToolResult, collect: (attachment: Attachment) => void): unknown {
+  const text: string[] = []
+  let files = 0
+  let images = 0
+  const push = (attachment: Attachment) => {
+    files += 1
+    if (attachment.mime.startsWith("image/")) images += 1
+    collect(attachment)
+  }
+  for (const block of result.content) {
+    switch (block.type) {
+      case "text":
+        text.push(block.text)
+        break
+      case "image":
+      case "audio":
+        push({ type: "file", mime: block.mimeType, url: dataUrl(block.mimeType, block.data) })
+        break
+      case "resource": {
+        if ("text" in block.resource) {
+          text.push(block.resource.text)
+          break
+        }
+        const mime = block.resource.mimeType ?? "application/octet-stream"
+        push({ type: "file", mime, url: dataUrl(mime, block.resource.blob), filename: lastSegment(block.resource.uri) })
+        break
+      }
+      case "resource_link":
+        // A link is a reference, not fetchable media; hand it to the program instead of the attachment channel.
+        text.push(`${block.name}: ${block.uri}`)
+        break
+    }
+  }
+
+  if (result.structuredContent !== undefined && result.structuredContent !== null) return result.structuredContent
+  if (text.length > 0) return text.join("\n")
+  if (files > 0) {
+    const noun = files === images ? "image" : "file"
+    return `[${files} ${noun}${files === 1 ? "" : "s"} attached to the result]`
+  }
+  return null
+}
+
+type Run = (input: unknown) => Effect.Effect<unknown, unknown>
+
+function toolTree(catalog: readonly CatalogEntry[], run: (entry: CatalogEntry) => Run) {
+  const tree: Record<string, Record<string, ToolDefinition>> = {}
+  for (const entry of catalog) {
+    const namespace = (tree[entry.server] ??= {})
+    namespace[entry.local] = SandboxTool.make({
+      description: entry.tool.def.description ?? "",
+      input: entry.tool.def.inputSchema as JsonSchema,
+      output: entry.tool.def.outputSchema as JsonSchema | undefined,
+      run: run(entry),
+    })
+  }
+  return tree
+}
+
+const invokeChildTool = Effect.fn("CodeMode.invokeChildTool")(function* (input: {
+  plugin: Plugin.Interface
+  entry: CatalogEntry
+  args: Record<string, unknown>
+  callID: string
+  ctx: Tool.Context
+}) {
+  yield* input.plugin.trigger(
+    "tool.execute.before",
+    { tool: input.entry.key, sessionID: input.ctx.sessionID, callID: input.callID },
+    { args: input.args },
+  )
+  const result: CallToolResult = yield* Effect.gen(function* () {
+    yield* input.ctx.ask({ permission: input.entry.key, metadata: {}, patterns: ["*"], always: ["*"] })
+    // Deliberately mirrors McpCatalog.convertTool's transport call so the MCP service stays free of tool-loop concerns.
+    return yield* Effect.promise(async () => {
+      const raw = await input.entry.tool.client.callTool(
+        { name: input.entry.tool.def.name, arguments: input.args },
+        CallToolResultSchema,
+        {
+          resetTimeoutOnProgress: true,
+          signal: input.ctx.abort,
+          timeout: input.entry.tool.timeout,
+          // The MCP SDK only sends a progress token when this hook is present, enabling timeout resets.
+          onprogress: () => {},
+        },
+      )
+      if (raw.isError)
+        throw new Error(
+          raw.content
+            .flatMap((item) => (item.type === "text" ? [item.text] : []))
+            .filter((text) => text.trim())
+            .join("\n\n") || "MCP tool returned an error",
+        )
+      return raw
+    })
+  }).pipe(
+    Effect.withSpan("Tool.execute", {
+      attributes: {
+        "tool.name": input.entry.key,
+        "tool.call_id": input.callID,
+        "session.id": input.ctx.sessionID,
+        "message.id": input.ctx.messageID,
+      },
+    }),
+  )
+  yield* input.plugin.trigger(
+    "tool.execute.after",
+    { tool: input.entry.key, sessionID: input.ctx.sessionID, callID: input.callID, args: input.args },
+    result,
+  )
+  return result
+})
+
+export const CodeModeTool = Tool.define(
+  CODE_MODE_TOOL,
+  Effect.gen(function* () {
+    const mcp = yield* MCP.Service
+    const agents = yield* Agent.Service
+    const sessions = yield* Session.Service
+    const plugin = yield* Plugin.Service
+
+    const init: Tool.DefWithoutID<typeof Parameters, Metadata> = {
+      description: DESCRIPTION,
+      parameters: Parameters,
+      execute: Effect.fn("CodeMode.execute")(function* (params, ctx) {
+        if (ctx.abort.aborted) {
+          return {
+            title: CODE_MODE_TOOL,
+            metadata: { toolCalls: [], error: true },
+            output: "Execution cancelled.",
+          } satisfies Tool.ExecuteResult<Metadata>
+        }
+        const agent = yield* agents.get(ctx.agent)
+        const session = yield* sessions.get(ctx.sessionID).pipe(Effect.orDie)
+        const ruleset = Permission.merge(agent.permission, session.permission ?? [])
+        const mcpTools = Permission.visibleTools(yield* mcp.tools(), ruleset)
+        const servers = Object.keys(yield* mcp.clients()).map(McpCatalog.sanitize)
+        const catalog = [...groupByServer(mcpTools, servers).values()].flat()
+
+        const calls: CallEntry[] = []
+        const attachments: Attachment[] = []
+        const publish = () =>
+          ctx.metadata({ title: CODE_MODE_TOOL, metadata: { toolCalls: calls.map((c) => ({ ...c })) } })
+
+        let childCalls = 0
+        const callTool = (entry: CatalogEntry) => (input: unknown) =>
+          Effect.gen(function* () {
+            childCalls += 1
+            const result = yield* invokeChildTool({
+              plugin,
+              entry,
+              args: (input ?? {}) as Record<string, unknown>,
+              callID: `${ctx.callID ?? entry.key}/${childCalls}`,
+              ctx,
+            })
+            return projectMcpResult(result, (attachment: Attachment) => void attachments.push(attachment))
+          }).pipe(
+            Effect.catchCause((cause) => {
+              if (Cause.hasInterruptsOnly(cause)) return Effect.interrupt
+              const error = Cause.squash(cause)
+              return Effect.fail(toolError(error instanceof Error ? error.message : String(error), error))
+            }),
+          )
+
+        const runtime = CodeMode.make({
+          tools: toolTree(catalog, callTool),
+          onToolCallStart: ({ index, name, input }) =>
+            Effect.suspend(() => {
+              const shown = (() => {
+                if (input === null || input === undefined) return
+                if (typeof input === "object" && !Array.isArray(input)) {
+                  const value = input as Record<string, unknown>
+                  return Object.keys(value).length > 0 ? value : undefined
+                }
+                return { input }
+              })()
+              calls[index] = { tool: name, status: "running", ...(shown ? { input: shown } : {}) }
+              return publish()
+            }),
+          onToolCallEnd: ({ index, outcome }) =>
+            Effect.suspend(() => {
+              const current = calls[index]
+              if (current) calls[index] = { ...current, status: outcome === "success" ? "completed" : "error" }
+              return publish()
+            }),
+        })
+
+        const abort = Effect.callback<void>((resume) => {
+          if (ctx.abort.aborted) return resume(Effect.void)
+          const handler = () => resume(Effect.void)
+          ctx.abort.addEventListener("abort", handler, { once: true })
+          return Effect.sync(() => ctx.abort.removeEventListener("abort", handler))
+        })
+        const cancelled = (): ExecuteResult => ({
+          ok: false,
+          error: { kind: "ExecutionFailure", message: "Execution cancelled." },
+          toolCalls: calls.map((call) => ({ name: call.tool })),
+        })
+
+        const result = yield* Effect.raceFirst(runtime.execute(params.code), abort.pipe(Effect.map(cancelled)))
+        const logs = result.logs ?? []
+        const attached = attachments.length > 0 ? { attachments } : {}
+        const hints = result.ok
+          ? []
+          : (result.error.suggestions ?? []).filter((hint) => !result.error.message.includes(hint))
+        const metadata: Metadata = result.ok ? { toolCalls: calls } : { toolCalls: calls, error: true }
+        let output: string
+        if (result.ok) {
+          if (typeof result.value === "string") output = result.value
+          else if (result.value === undefined) output = "undefined"
+          else {
+            try {
+              output = JSON.stringify(result.value, null, 2) ?? String(result.value)
+            } catch {
+              output = String(result.value)
+            }
+          }
+        } else {
+          output = [result.error.message, ...hints].join("\n")
+        }
+        if (logs.length > 0)
+          output = output.length > 0 ? `${output}\n\nLogs:\n${logs.join("\n")}` : `Logs:\n${logs.join("\n")}`
+
+        return {
+          title: CODE_MODE_TOOL,
+          metadata,
+          output,
+          ...attached,
+        } satisfies Tool.ExecuteResult<Metadata>
+      }),
+    }
+    return init
+  }),
+)