refactor(session): align prompt input types with their schemas (#25178)

2 files changed, 14 insertions, 25 deletions

diff --git a/packages/opencode/src/server/routes/instance/httpapi/handlers/session.ts b/packages/opencode/src/server/routes/instance/httpapi/handlers/session.ts
index c4def3e74..91afd0045 100644
--- a/packages/opencode/src/server/routes/instance/httpapi/handlers/session.ts
+++ b/packages/opencode/src/server/routes/instance/httpapi/handlers/session.ts
@@ -269,7 +269,7 @@ export const sessionHandlers = HttpApiBuilder.group(InstanceHttpApi, "session",
               promptSvc.prompt({
                 ...ctx.payload,
                 sessionID: ctx.params.sessionID,
-              } as unknown as SessionPrompt.PromptInput),
+              }),
             ),
           ),
         ).pipe(
@@ -288,7 +288,7 @@ export const sessionHandlers = HttpApiBuilder.group(InstanceHttpApi, "session",
       yield* Effect.sync(() => {
         bridge.fork(
           promptSvc
-            .prompt({ ...ctx.payload, sessionID: ctx.params.sessionID } as unknown as SessionPrompt.PromptInput)
+            .prompt({ ...ctx.payload, sessionID: ctx.params.sessionID })
             .pipe(
               Effect.catchCause((error) =>
                 Effect.sync(() => {
@@ -309,14 +309,14 @@ export const sessionHandlers = HttpApiBuilder.group(InstanceHttpApi, "session",
       params: { sessionID: SessionID }
       payload: typeof CommandPayload.Type
     }) {
-      return yield* promptSvc.command({ ...ctx.payload, sessionID: ctx.params.sessionID } as SessionPrompt.CommandInput)
+      return yield* promptSvc.command({ ...ctx.payload, sessionID: ctx.params.sessionID })
     })
 
     const shell = Effect.fn("SessionHttpApi.shell")(function* (ctx: {
       params: { sessionID: SessionID }
       payload: typeof ShellPayload.Type
     }) {
-      return yield* promptSvc.shell({ ...ctx.payload, sessionID: ctx.params.sessionID } as SessionPrompt.ShellInput)
+      return yield* promptSvc.shell({ ...ctx.payload, sessionID: ctx.params.sessionID })
     })
 
     const revert = Effect.fn("SessionHttpApi.revert")(function* (ctx: {
diff --git a/packages/opencode/src/session/prompt.ts b/packages/opencode/src/session/prompt.ts
index c4d867322..155b86b58 100644
--- a/packages/opencode/src/session/prompt.ts
+++ b/packages/opencode/src/session/prompt.ts
@@ -45,7 +45,7 @@ import { AppFileSystem } from "@opencode-ai/core/filesystem"
 import { Truncate } from "@/tool/truncate"
 import { decodeDataUrl } from "@/util/data-url"
 import { Process } from "@/util/process"
-import { Cause, Effect, Exit, Latch, Layer, Option, Scope, Context, Schema } from "effect"
+import { Cause, Effect, Exit, Latch, Layer, Option, Scope, Context, Schema, Types } from "effect"
 import { zod } from "@/util/effect-zod"
 import { withStatics } from "@/util/schema"
 import * as EffectLogger from "@opencode-ai/core/effect/logger"
@@ -127,7 +127,7 @@ export const layer = Layer.effect(
 
     const resolvePromptParts = Effect.fn("SessionPrompt.resolvePromptParts")(function* (template: string) {
       const ctx = yield* InstanceState.context
-      const parts: PromptInput["parts"] = [{ type: "text", text: template }]
+      const parts: Types.DeepMutable<PromptInput["parts"]> = [{ type: "text", text: template }]
       const files = ConfigMarkdown.files(template)
       const seen = new Set<string>()
       yield* Effect.forEach(
@@ -1012,7 +1012,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
             case "file:": {
               log.info("file", { mime: part.mime })
               const filepath = fileURLToPath(part.url)
-              if (yield* fsys.isDir(filepath)) part.mime = "application/x-directory"
+              const mime = (yield* fsys.isDir(filepath)) ? "application/x-directory" : part.mime
 
               const { read } = yield* registry.named()
               const execRead = (args: Parameters<typeof read.execute>[0], extra?: Tool.Context["extra"]) => {
@@ -1031,7 +1031,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                   .pipe(Effect.onInterrupt(() => Effect.sync(() => controller.abort())))
               }
 
-              if (part.mime === "text/plain") {
+              if (mime === "text/plain") {
                 let offset: number | undefined
                 let limit: number | undefined
                 const range = { start: url.searchParams.get("start"), end: url.searchParams.get("end") }
@@ -1089,7 +1089,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                       })),
                     )
                   } else {
-                    pieces.push({ ...part, messageID: info.id, sessionID: input.sessionID })
+                    pieces.push({ ...part, mime, messageID: info.id, sessionID: input.sessionID })
                   }
                 } else {
                   const error = Cause.squash(exit.cause)
@@ -1110,7 +1110,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                 return pieces
               }
 
-              if (part.mime === "application/x-directory") {
+              if (mime === "application/x-directory") {
                 const args = { filePath: filepath }
                 const exit = yield* execRead(args).pipe(Effect.exit)
                 if (Exit.isFailure(exit)) {
@@ -1146,7 +1146,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                     synthetic: true,
                     text: exit.value.output,
                   },
-                  { ...part, messageID: info.id, sessionID: input.sessionID },
+                  { ...part, mime, messageID: info.id, sessionID: input.sessionID },
                 ]
               }
 
@@ -1164,9 +1164,9 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                   sessionID: input.sessionID,
                   type: "file",
                   url:
-                    `data:${part.mime};base64,` +
+                    `data:${mime};base64,` +
                     Buffer.from(yield* fsys.readFile(filepath).pipe(Effect.catch(Effect.die))).toString("base64"),
-                  mime: part.mime,
+                  mime,
                   filename: part.filename!,
                   source: part.source,
                 },
@@ -1700,18 +1700,7 @@ export const PromptInput = Schema.Struct({
     ]).annotate({ discriminator: "type" }),
   ),
 }).pipe(withStatics((s) => ({ zod: zod(s) })))
-// `z.discriminatedUnion` erases the discriminated members' shapes back to
-// `{}` when walked from the generic `z.ZodType` input. Restore the precise
-// `parts` type from the exported Schema input types so callers see a proper
-// tagged union.
-type PartInputUnion =
-  | MessageV2.TextPartInput
-  | MessageV2.FilePartInput
-  | MessageV2.AgentPartInput
-  | MessageV2.SubtaskPartInput
-export type PromptInput = Omit<Schema.Schema.Type<typeof PromptInput>, "parts"> & {
-  parts: PartInputUnion[]
-}
+export type PromptInput = Schema.Schema.Type<typeof PromptInput>
 
 export class LoopInput extends Schema.Class<LoopInput>("SessionPrompt.LoopInput")({
   sessionID: SessionID,