feat (ai): introduce dynamic tools (#7595)

## Background

MCP tools that are defined without providing schemas have no type
information at development time. This breaks type inference, especially
for UI parts when dynamic MCP tools and regular tools are mixed.
Similarly, tools that are defined at app runtime (e.g. user supplied
functions) are conflicting with typing.

## Summary

* introduce `dynamic` tool type
* introduce `dynamicTool` helper
* mcp client tools without schemas are dynamic tools
* change tool call, result, and error unions to support dynamic tools
(breaking change)
* add dynamic flag to ui message chunks
* add `dynamic-tool` ui message part

## Verification

- [x] manually test behavior and type inference on generate text example
with dynamic tools
- [x] manually test behavior and type inference on stream text example
with dynamic tools
- [x] manually test behavior and type inference on ui examples that
mixes static tool and dynamic tools

## Future work
Add useChat onToolCall for dynamic tools

Author: lgrammel

.changeset/bright-dodos-smash.md

@@ -0,0 +1,6 @@
+---
+'@ai-sdk/provider-utils': patch
+'ai': patch
+---
+
+feat (ai): introduce dynamic tools

examples/ai-core/src/generate-text/amazon-bedrock-cache-point-tool-call.ts

@@ -140,6 +140,10 @@ async function main() {
 
   // typed tool calls:
   for (const toolCall of result.toolCalls) {
+    if (toolCall.dynamic) {
+      continue;
+    }
+
     switch (toolCall.toolName) {
       case 'weather': {
         toolCall.input.location; // string
@@ -150,6 +154,10 @@ async function main() {
 
   // typed tool results for tools with execute method:
   for (const toolResult of result.toolResults) {
+    if (toolResult.dynamic) {
+      continue;
+    }
+
     switch (toolResult.toolName) {
       case 'weather': {
         toolResult.input.location; // string

examples/ai-core/src/generate-text/amazon-bedrock-tool-call.ts

@@ -19,6 +19,10 @@ async function main() {
 
   // typed tool calls:
   for (const toolCall of result.toolCalls) {
+    if (toolCall.dynamic) {
+      continue;
+    }
+
     switch (toolCall.toolName) {
       case 'cityAttractions': {
         toolCall.input.city; // string
@@ -34,6 +38,10 @@ async function main() {
 
   // typed tool results for tools with execute method:
   for (const toolResult of result.toolResults) {
+    if (toolResult.dynamic) {
+      continue;
+    }
+
     switch (toolResult.toolName) {
       // NOT AVAILABLE (NO EXECUTE METHOD)
       // case 'cityAttractions': {

examples/ai-core/src/generate-text/anthropic-tool-call.ts

@@ -20,6 +20,10 @@ async function main() {
 
   // typed tool calls:
   for (const toolCall of result.toolCalls) {
+    if (toolCall.dynamic) {
+      continue;
+    }
+
     switch (toolCall.toolName) {
       case 'cityAttractions': {
         toolCall.input.city; // string
@@ -35,6 +39,10 @@ async function main() {
 
   // typed tool results for tools with execute method:
   for (const toolResult of result.toolResults) {
+    if (toolResult.dynamic) {
+      continue;
+    }
+
     switch (toolResult.toolName) {
       // NOT AVAILABLE (NO EXECUTE METHOD)
       // case 'cityAttractions': {

examples/ai-core/src/generate-text/anthropic-web-search.ts

@@ -29,6 +29,10 @@ async function main() {
 
   // typed tool results for tools with execute method:
   for (const toolResult of result.toolResults) {
+    if (toolResult.dynamic) {
+      continue;
+    }
+
     switch (toolResult.toolName) {
       case 'web_search': {
         toolResult.input.query; // string

examples/ai-core/src/generate-text/cerebras-tool-call.ts

@@ -20,6 +20,10 @@ async function main() {
 
   // typed tool calls:
   for (const toolCall of result.toolCalls) {
+    if (toolCall.dynamic) {
+      continue;
+    }
+
     switch (toolCall.toolName) {
       case 'cityAttractions': {
         toolCall.input.city; // string
@@ -35,6 +39,10 @@ async function main() {
 
   // typed tool results for tools with execute method:
   for (const toolResult of result.toolResults) {
+    if (toolResult.dynamic) {
+      continue;
+    }
+
     switch (toolResult.toolName) {
       // NOT AVAILABLE (NO EXECUTE METHOD)
       // case 'cityAttractions': {

examples/ai-core/src/generate-text/cohere-tool-call.ts

@@ -20,6 +20,10 @@ async function main() {
 
   // typed tool calls:
   for (const toolCall of result.toolCalls) {
+    if (toolCall.dynamic) {
+      continue;
+    }
+
     switch (toolCall.toolName) {
       case 'cityAttractions': {
         toolCall.input.city; // string
@@ -35,6 +39,10 @@ async function main() {
 
   // typed tool results for tools with execute method:
   for (const toolResult of result.toolResults) {
+    if (toolResult.dynamic) {
+      continue;
+    }
+
     switch (toolResult.toolName) {
       // NOT AVAILABLE (NO EXECUTE METHOD)
       // case 'cityAttractions': {

examples/ai-core/src/generate-text/deepinfra-tool-call.ts

@@ -22,6 +22,10 @@ async function main() {
 
   // typed tool calls:
   for (const toolCall of result.toolCalls) {
+    if (toolCall.dynamic) {
+      continue;
+    }
+
     switch (toolCall.toolName) {
       case 'cityAttractions': {
         toolCall.input.city; // string
@@ -37,6 +41,10 @@ async function main() {
 
   // typed tool results for tools with execute method:
   for (const toolResult of result.toolResults) {
+    if (toolResult.dynamic) {
+      continue;
+    }
+
     switch (toolResult.toolName) {
       // NOT AVAILABLE (NO EXECUTE METHOD)
       // case 'cityAttractions': {

examples/ai-core/src/generate-text/gateway-tool-call.ts

@@ -19,6 +19,10 @@ async function main() {
 
   // typed tool calls:
   for (const toolCall of result.toolCalls) {
+    if (toolCall.dynamic) {
+      continue;
+    }
+
     switch (toolCall.toolName) {
       case 'cityAttractions': {
         toolCall.input.city; // string
@@ -34,6 +38,10 @@ async function main() {
 
   // typed tool results for tools with execute method:
   for (const toolResult of result.toolResults) {
+    if (toolResult.dynamic) {
+      continue;
+    }
+
     switch (toolResult.toolName) {
       // NOT AVAILABLE (NO EXECUTE METHOD)
       // case 'cityAttractions': {

examples/ai-core/src/generate-text/google-tool-call.ts

@@ -20,6 +20,10 @@ async function main() {
 
   // typed tool calls:
   for (const toolCall of result.toolCalls) {
+    if (toolCall.dynamic) {
+      continue;
+    }
+
     switch (toolCall.toolName) {
       case 'cityAttractions': {
         toolCall.input.city; // string
@@ -35,6 +39,10 @@ async function main() {
 
   // typed tool results for tools with execute method:
   for (const toolResult of result.toolResults) {
+    if (toolResult.dynamic) {
+      continue;
+    }
+
     switch (toolResult.toolName) {
       // NOT AVAILABLE (NO EXECUTE METHOD)
       // case 'cityAttractions': {