refactor(tools): unify tool APIs and result handling (#38367)

packages/ai/src/protocols/anthropic-messages.ts

@@ -330,7 +330,10 @@ const lowerServerToolResult = Effect.fn("AnthropicMessages.lowerServerToolResult
   const wireType = serverToolResultType(part.name)
   if (!wireType)
     return yield* invalid(`Anthropic Messages does not know how to round-trip server tool result for ${part.name}`)
-  return { type: wireType, tool_use_id: part.id, content: part.result.value } satisfies AnthropicServerToolResultBlock
+  // Prefer the provider-owned replay payload; fall back to the result value for
+  // histories constructed directly from provider events.
+  const payload = part.providerMetadata?.anthropic?.["result"] ?? part.result.value
+  return { type: wireType, tool_use_id: part.id, content: payload } satisfies AnthropicServerToolResultBlock
 })
 
 const lowerMedia = Effect.fn("AnthropicMessages.lowerMedia")(function* (part: MediaPart) {
@@ -682,7 +685,9 @@ const serverToolResultEvent = (block: NonNullable<AnthropicEvent["content_block"
     name: SERVER_TOOL_RESULT_NAMES[block.type],
     result: isError ? { type: "error", value: block.content } : { type: "json", value: block.content },
     providerExecuted: true,
-    providerMetadata: anthropicMetadata({ blockType: block.type }),
+    // The complete payload is irreducible provider replay state: subsequent
+    // stateless requests must round-trip the typed result block verbatim.
+    providerMetadata: anthropicMetadata({ blockType: block.type, result: block.content }),
   })
 }
 

packages/ai/src/protocols/bedrock-converse.ts

@@ -392,8 +392,13 @@ const fromRequest = Effect.fn("BedrockConverse.fromRequest")(function* (request:
   // tools → system → messages order to favour the highest-impact prefixes.
   const breakpoints = BedrockCache.breakpoints()
   const toolConfig =
-    request.tools.length > 0 && request.toolChoice?.type !== "none"
-      ? { tools: lowerTools(request.model.compatibility?.toolSchema, breakpoints, request.tools), toolChoice }
+    request.tools.length > 0
+      ? {
+          tools: lowerTools(request.model.compatibility?.toolSchema, breakpoints, request.tools),
+          // Converse has no native "none". Keep definitions stable for prompt
+          // caching and omit only the unsupported choice.
+          toolChoice,
+        }
       : undefined
   const system = request.system.length === 0 ? undefined : lowerSystem(breakpoints, request.system)
   const messages = yield* lowerMessages(request, breakpoints)

packages/ai/test/provider/anthropic-messages.test.ts

@@ -664,7 +664,14 @@ describe("Anthropic Messages route", () => {
         name: "web_search",
         result: { type: "json", value: [{ type: "web_search_result", url: "https://example.com", title: "Example" }] },
         providerExecuted: true,
-        providerMetadata: { anthropic: { blockType: "web_search_tool_result" } },
+        // The complete payload rides in provider metadata as irreducible replay
+        // state for later stateless requests.
+        providerMetadata: {
+          anthropic: {
+            blockType: "web_search_tool_result",
+            result: [{ type: "web_search_result", url: "https://example.com", title: "Example" }],
+          },
+        },
       })
       expect(response.text).toBe("Found it.")
       expect(response.events.at(-1)).toMatchObject({ type: "finish", reason: "stop" })

packages/ai/test/provider/bedrock-converse.test.ts

@@ -154,6 +154,36 @@ describe("Bedrock Converse route", () => {
     }),
   )
 
+  it.effect("keeps tools and omits the unsupported choice when tool choice is none", () =>
+    Effect.gen(function* () {
+      const prepared = yield* LLMClient.prepare(
+        LLM.updateRequest(baseRequest, {
+          tools: [
+            {
+              name: "lookup",
+              description: "Lookup data",
+              inputSchema: { type: "object", properties: { query: { type: "string" } } },
+            },
+          ],
+          toolChoice: ToolChoice.make({ type: "none" }),
+        }),
+      )
+
+      expect(prepared.body.toolConfig).toMatchObject({
+        tools: [
+          {
+            toolSpec: {
+              name: "lookup",
+              description: "Lookup data",
+              inputSchema: { json: { type: "object", properties: { query: { type: "string" } } } },
+            },
+          },
+        ],
+      })
+      expect(prepared.body.toolConfig?.toolChoice).toBeUndefined()
+    }),
+  )
+
   it.effect("lowers assistant tool-call + tool-result message history", () =>
     Effect.gen(function* () {
       const prepared = yield* LLMClient.prepare(