\n
TypeScript
\n\n```typescript\nsession.on(\"assistant.usage\", (event) => {\n const { model, inputTokens, outputTokens, cost } = event.data;\n console.log(\n `${model}: in=${inputTokens ?? 0} out=${outputTokens ?? 0} cost=${cost ?? 0}`,\n );\n});\n```\n\n
\n\n
Python
\n\n```python\ndef on_usage(event):\n if event.type == SessionEventType.ASSISTANT_USAGE:\n data = event.data\n print(f\"{data.model}: in={data.input_tokens or 0} out={data.output_tokens or 0} cost={data.cost or 0}\")\n\nsession.on(on_usage)\n```\n\n
\n\n
Go
\n\n```golang\nsession.On(func(event copilot.SessionEvent) {\n d, ok := event.Data.(*copilot.AssistantUsageData)\n if !ok {\n return\n }\n in, out, cost := int64(0), int64(0), float64(0)\n if d.InputTokens != nil {\n in = *d.InputTokens\n }\n if d.OutputTokens != nil {\n out = *d.OutputTokens\n }\n if d.Cost != nil {\n cost = *d.Cost\n }\n fmt.Printf(\"%s: in=%d out=%d cost=%g\\n\", d.Model, in, out, cost)\n})\n```\n\n
\n\n
.NET
\n\n```csharp\nsession.On
(evt =>\n{\n var data = evt.Data;\n Console.WriteLine(\n $\"{data.Model}: in={data.InputTokens ?? 0} out={data.OutputTokens ?? 0} cost={data.Cost ?? 0}\");\n});\n```\n\n\n\n
Java
\n\n\n\n```java\nsession.on(AssistantUsageEvent.class, event -> {\n var data = event.getData();\n long in = data.inputTokens() != null ? data.inputTokens() : 0;\n long out = data.outputTokens() != null ? data.outputTokens() : 0;\n double cost = data.cost() != null ? data.cost() : 0.0;\n System.out.printf(\"%s: in=%d out=%d cost=%s%n\", data.model(), in, out, cost);\n});\n```\n\n
\n\n
Rust
\n\n```rust\nuse github_copilot_sdk::session_events::AssistantUsageData;\n\nlet mut events = session.subscribe();\nwhile let Ok(event) = events.recv().await {\n if event.event_type == \"assistant.usage\" {\n if let Some(data) = event.typed_data::
() {\n println!(\n \"{}: in={} out={} cost={}\",\n data.model,\n data.input_tokens.unwrap_or(0),\n data.output_tokens.unwrap_or(0),\n data.cost.unwrap_or(0.0),\n );\n }\n }\n}\n```\n\n\n\n
\n
TypeScript
\n\n```typescript\nsession.on(\"session.usage_info\", (event) => {\n const { currentTokens, tokenLimit } = event.data;\n const pct = Math.round((currentTokens / tokenLimit) * 100);\n console.log(`Context: ${currentTokens}/${tokenLimit} (${pct}%)`);\n});\n```\n\n
\n\n
Python
\n\n```python\ndef on_usage_info(event):\n if event.type == SessionEventType.SESSION_USAGE_INFO:\n data = event.data\n pct = round(data.current_tokens / data.token_limit * 100)\n print(f\"Context: {data.current_tokens}/{data.token_limit} ({pct}%)\")\n\nsession.on(on_usage_info)\n```\n\n
\n\n
Go
\n\n```golang\nsession.On(func(event copilot.SessionEvent) {\n d, ok := event.Data.(*copilot.SessionUsageInfoData)\n if !ok {\n return\n }\n pct := int(float64(d.CurrentTokens) / float64(d.TokenLimit) * 100)\n fmt.Printf(\"Context: %d/%d (%d%%)\\n\", d.CurrentTokens, d.TokenLimit, pct)\n})\n```\n\n
\n\n
.NET
\n\n```csharp\nsession.On
(evt =>\n{\n var pct = (int)Math.Round((double)evt.Data.CurrentTokens / evt.Data.TokenLimit * 100);\n Console.WriteLine($\"Context: {evt.Data.CurrentTokens}/{evt.Data.TokenLimit} ({pct}%)\");\n});\n```\n\n\n\n
Java
\n\n\n\n```java\nsession.on(SessionUsageInfoEvent.class, event -> {\n var data = event.getData();\n long pct = Math.round((double) data.currentTokens() / data.tokenLimit() * 100);\n System.out.printf(\"Context: %d/%d (%d%%)%n\", data.currentTokens(), data.tokenLimit(), pct);\n});\n```\n\n
\n\n
Rust
\n\n```rust\nuse github_copilot_sdk::session_events::SessionUsageInfoData;\n\nlet mut events = session.subscribe();\nwhile let Ok(event) = events.recv().await {\n if event.event_type == \"session.usage_info\" {\n if let Some(data) = event.typed_data::
() {\n let pct = (data.current_tokens as f64 / data.token_limit as f64 * 100.0) as i64;\n println!(\"Context: {}/{} ({}%)\", data.current_tokens, data.token_limit, pct);\n }\n }\n}\n```\n\n\n\n
\n
TypeScript
\n\n```typescript\nconst { contextInfo } = await session.rpc.metadata.contextInfo({\n promptTokenLimit: 0,\n outputTokenLimit: 0,\n});\n\nif (contextInfo) {\n console.log(\n `Total ${contextInfo.totalTokens}/${contextInfo.promptTokenLimit} ` +\n `(system=${contextInfo.systemTokens}, conversation=${contextInfo.conversationTokens})`,\n );\n}\n```\n\n
\n\n
Python
\n\n```python\nresult = await session.rpc.metadata.context_info(\n MetadataContextInfoRequest(prompt_token_limit=0, output_token_limit=0)\n)\ninfo = result.context_info\n\nif info is not None:\n print(\n f\"Total {info.total_tokens}/{info.prompt_token_limit} \"\n f\"(system={info.system_tokens}, conversation={info.conversation_tokens})\"\n )\n```\n\n
\n\n
Go
\n\n```golang\nresult, _ := session.RPC.Metadata.ContextInfo(ctx, &rpc.MetadataContextInfoRequest{\n PromptTokenLimit: 0,\n OutputTokenLimit: 0,\n})\n\nif info := result.ContextInfo; info != nil {\n fmt.Printf(\"Total %d/%d (system=%d, conversation=%d)\\n\",\n info.TotalTokens, info.PromptTokenLimit, info.SystemTokens, info.ConversationTokens)\n}\n```\n\n
\n\n
.NET
\n\n```csharp\nvar result = await session.Rpc.Metadata.ContextInfoAsync(promptTokenLimit: 0, outputTokenLimit: 0);\nvar info = result.ContextInfo;\n\nif (info is not null)\n{\n Console.WriteLine(\n $\"Total {info.TotalTokens}/{info.PromptTokenLimit} \" +\n $\"(system={info.SystemTokens}, conversation={info.ConversationTokens})\");\n}\n```\n\n
\n\n
Java
\n\n\n\n```java\nvar result = session.getRpc().metadata\n .contextInfo(new SessionMetadataContextInfoParams(null, 0L, 0L, null))\n .join();\nvar info = result.contextInfo();\n\nif (info != null) {\n System.out.printf(\"Total %d/%d (system=%d, conversation=%d)%n\",\n info.totalTokens(), info.promptTokenLimit(), info.systemTokens(), info.conversationTokens());\n}\n```\n\n
\n\n
Rust
\n\n```rust\nuse github_copilot_sdk::rpc::MetadataContextInfoRequest;\n\nlet result = session\n .rpc()\n .metadata()\n .context_info(MetadataContextInfoRequest {\n prompt_token_limit: 0,\n output_token_limit: 0,\n selected_model: None,\n })\n .await?;\n\nif let Some(info) = result.context_info {\n println!(\n \"Total {}/{} (system={}, conversation={})\",\n info.total_tokens, info.prompt_token_limit, info.system_tokens, info.conversation_tokens,\n );\n}\n```\n\n
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