The whole hunk
from line 12, old and new numbered
/
lines
from line 12
1212 - claude-mythos-5-1
1313 - claude-fable-5
1414 - claude-mythos-5
15 - claude-opus-5-5
1516 - claude-opus-5
1617 - claude-sonnet-5
1718 - claude-opus-4-8
from line 23
2223 Google Cloud: ga
2324 Microsoft Foundry: beta
2425 details:
26 - On the Claude API and Google Cloud, Claude Opus 5.5 supports computer use only through the `computer_toolset_20260801` toolset and returns an error for the earlier `computer_20251124` tool version. To move an existing integration, see [Migrate from `computer_20251124`](https://platform.claude.com/docs/en/agents-and-tools/tool-use/computer-use-tool#migrate-from-computer-20251124).
27 - On Amazon Bedrock, Claude Opus 5.5 accepts the earlier `computer_20251124` tool version as Claude Opus 5 does.
2528 - Claude Opus 4.7, Claude Opus 4.6, Claude Sonnet 4.6, and Claude Opus 4.5 support computer use only through the earlier `computer_20251124` tool version, which requires a beta header; see [Earlier tool versions](https://platform.claude.com/docs/en/agents-and-tools/tool-use/computer-use-tool#earlier-tool-versions).
2629 - Platforms other than the Claude API and Google Cloud currently offer only the [earlier beta tool versions](https://platform.claude.com/docs/en/agents-and-tools/tool-use/computer-use-tool#earlier-tool-versions).
2730---
from line 73
7073 -H "x-api-key: $ANTHROPIC_API_KEY" \
7174 -H "anthropic-version: 2023-06-01" \
7275 -d '{
73 "model": "claude-opus-5",
76 "model": "claude-opus-5-5",
7477 "max_tokens": 1024,
7578 "tools": [
7679 {
from line 99
9699
97100 ```bash CLI
98101 ant messages create <<'YAML'
99 model: claude-opus-5
102 model: claude-opus-5-5
100103 max_tokens: 1024
101104 tools:
102105 - type: computer_toolset_20260801
from line 117
114117 client = anthropic.Anthropic()
115118
116119 response = client.messages.create(
117 model="claude-opus-5",
120 model="claude-opus-5-5",
118121 max_tokens=1024,
119122 tools=[
120123 {"type": "computer_toolset_20260801"},
from line 133
130133 const client = new Anthropic();
131134
132135 const response = await client.messages.create({
133 model: "claude-opus-5",
136 model: "claude-opus-5-5",
134137 max_tokens: 1024,
135138 tools: [
136139 {
from line 159
156159
157160 var parameters = new MessageCreateParams
158161 {
159 Model = Model.ClaudeOpus5,
162 Model = Model.ClaudeOpus5_5,
160163 MaxTokens = 1024,
161164 Tools =
162165 [
from line 185
182185 client := anthropic.NewClient()
183186
184187 response, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
185 Model: anthropic.ModelClaudeOpus5,
188 Model: anthropic.ModelClaudeOpus5_5,
186189 MaxTokens: 1024,
187190 Tools: []anthropic.ToolUnionParam{
188191 {OfComputerToolset20260801: &anthropic.ComputerToolset20260801Param{}},
from line 212
209212 AnthropicClient client = AnthropicOkHttpClient.fromEnv();
210213
211214 MessageCreateParams params = MessageCreateParams.builder()
212 .model(Model.CLAUDE_OPUS_5)
215 .model(Model.CLAUDE_OPUS_5_5)
213216 .maxTokens(1024L)
214217 .addTool(ComputerToolset20260801.builder().build())
215218 .addTool(ToolTextEditor20250728.builder().build())
from line 233
230233 messages: [
231234 ['role' => 'user', 'content' => 'Save a picture of a cat to my desktop.'],
232235 ],
233 model: 'claude-opus-5',
236 model: 'claude-opus-5-5',
234237 tools: [
235238 ['type' => 'computer_toolset_20260801'],
236239 [
from line 254
251254 client = Anthropic::Client.new
252255
253256 response = client.messages.create(
254 model: "claude-opus-5",
257 model: "claude-opus-5-5",
255258 max_tokens: 1024,
256259 tools: [
257260 { type: "computer_toolset_20260801" },
from line 283
280283 "id": "msg_01UZ3bXcQH8mTqNhVfL9eK2p",
281284 "type": "message",
282285 "role": "assistant",
283 "model": "claude-opus-5",
286 "model": "claude-opus-5-5",
284287 "content": [
285288 {
286289 "type": "text",
from line 1828
18251828
18261829* Place one `cache_control` breakpoint after the system prompt and tool definitions, and up to three more on the last `tool_result` block of each of the most recent turns, advancing them each turn. Within a [batch action](https://platform.claude.com/docs/en/agents-and-tools/tool-use/computer-use-tool#batch-actions), markers on several blocks act as a single breakpoint but each still counts toward the limit of four, so use one per turn.
18271830* Prune old screenshots in *batches*, not one each turn. Dropping a screenshot every turn changes the prefix every turn and invalidates the cache. A reasonable default is to keep the last three screenshots and prune every 25 turns, so the prefix stays byte-identical between prune events; if your screenshots exceed 2000 px on either side, choose an interval that keeps each request at 20 or fewer images.
1828* On Claude Fable 5.1, avoid pruning on the client: removing an earlier screenshot [invalidates every later thinking block](https://platform.claude.com/docs/en/build-with-claude/thinking#preserved-in-conversation) in every request that still carries those turns. Resize screenshots to 2000 px or less per side instead, and use server-side [tool result clearing](https://platform.claude.com/docs/en/build-with-claude/context-editing#tool-result-clearing) to drop old ones from the context. If you must prune, keep [`prefix_mismatch_behavior: "drop_block"`](https://platform.claude.com/docs/en/build-with-claude/thinking#preserved-thinking-controls) set from then on; after each prune, Claude continues without the thinking produced since the pruned screenshot, on that request and every later one.
1831* On Claude Fable 5.1 and Claude Opus 5.5, avoid pruning on the client: removing an earlier screenshot [invalidates every later thinking block](https://platform.claude.com/docs/en/build-with-claude/thinking#preserved-in-conversation) in every request that still carries those turns. Resize screenshots to 2000 px or less per side instead, and use server-side [tool result clearing](https://platform.claude.com/docs/en/build-with-claude/context-editing#tool-result-clearing) to drop old ones from the context. If you must prune, keep [`prefix_mismatch_behavior: "drop_block"`](https://platform.claude.com/docs/en/build-with-claude/thinking#preserved-thinking-controls) set from then on; after each prune, Claude continues without the thinking produced since the pruned screenshot, on that request and every later one.
18291832
18301833### Diagnose click issues
18311834
from line 2115
21122115
21132116## Migrate from `computer_20251124`
21142117
2115Upgrading from `computer_20251124` to the toolset is optional: the models listed for `computer_20251124` under [Earlier tool versions](https://platform.claude.com/docs/en/agents-and-tools/tool-use/computer-use-tool#earlier-tool-versions) keep accepting it with its beta header, so an existing integration keeps working until you change it. To upgrade, make the following changes together:
2118Upgrading from `computer_20251124` to the toolset is optional: the models listed for `computer_20251124` under [Earlier tool versions](https://platform.claude.com/docs/en/agents-and-tools/tool-use/computer-use-tool#earlier-tool-versions) keep accepting it with its beta header, so an existing integration keeps working until you change it. Claude Opus 5.5 is the exception on the Claude API and Google Cloud: there it accepts only the toolset, so upgrade an integration before moving it to that model. On Amazon Bedrock it keeps accepting `computer_20251124`. To upgrade, make the following changes together:
21162119
211721201. **Remove the beta header.** Drop `anthropic-beta: computer-use-2025-11-24` from your requests. In the SDKs, remove the `betas` parameter and call the Messages API through the standard client rather than the beta namespace.
211821212. **Change the `tools` entry.** Set `type` to `computer_toolset_20260801` and delete `name`, `display_width_px`, `display_height_px`, `display_number`, and `enable_zoom`. The toolset rejects each of these fields.
from line 2177
21742177
21752178| Tool version | Beta header | Use with | Parameters |
21762179| ------------------- | ------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------- |
2177| `computer_20251124` | `computer-use-2025-11-24` | Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5, Claude Sonnet 5, Claude Opus 4.8, Claude Opus 4.7, Claude Opus 4.6, Claude Sonnet 4.6, and Claude Opus 4.5 | [API reference](https://platform.claude.com/docs/en/api/beta/messages/create) |
2180| `computer_20251124` | `computer-use-2025-11-24` | Claude Fable 5.1, Claude Mythos 5.1, Claude Fable 5, Claude Mythos 5, Claude Opus 5, Claude Sonnet 5, Claude Opus 4.8, Claude Opus 4.7, Claude Opus 4.6, Claude Sonnet 4.6, and Claude Opus 4.5; on Amazon Bedrock, also Claude Opus 5.5 | [API reference](https://platform.claude.com/docs/en/api/beta/messages/create) |
21782181| `computer_20250124` | `computer-use-2025-01-24` | Claude Sonnet 4.5, Claude Haiku 4.5, Claude Opus 4.1 ([retired, except on Bedrock and Google Cloud](https://platform.claude.com/docs/en/about-claude/model-deprecations)), Claude Sonnet 4 ([retired, except on Bedrock and Google Cloud](https://platform.claude.com/docs/en/about-claude/model-deprecations)), and Claude Opus 4 ([retired, except on Google Cloud](https://platform.claude.com/docs/en/about-claude/model-deprecations)) | [API reference](https://platform.claude.com/docs/en/api/beta/messages/create) |
21792182
21802183***