Update Session changedapi/beta/sessions/update
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Lines−267removed
From line
129
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14 Aug 2026
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129129
130130- `agent: optional BetaManagedAgentsSessionAgentUpdate`
131131
132 Mid-session agent configuration update. Only `tools` and `mcp_servers` are updatable. Full replacement: the provided array becomes the new value. To preserve existing entries, GET the session, modify the array, and POST it back.
132 Agent configuration update. Only `tools` and `mcp_servers` are updatable mid-session. Only valid for sessions created from an agent or deployment reference. The session must not be running.
133133
134134 - `mcp_servers: optional array of BetaManagedAgentsURLMCPServerParams`
135135
from line 179
179179
180180 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
181181
182 Permission policy for tool execution.
182 Permission policy for this tool. Controls whether tool calls are auto-approved or require confirmation.
183183
184184 - `BetaManagedAgentsAlwaysAllowPolicy object`
185185
from line 215
215215
216216 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
217217
218 Permission policy for tool execution.
218 Permission policy for this tool. Controls whether tool calls are auto-approved or require confirmation.
219219
220220 - `BetaManagedAgentsAlwaysAllowPolicy object`
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from line 245
245245
246246 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
247247
248 Permission policy for tool execution.
248 Permission policy for this tool. Controls whether tool calls are auto-approved or require confirmation.
249249
250250 - `BetaManagedAgentsAlwaysAllowPolicy object`
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from line 275
275275
276276 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
277277
278 Permission policy for tool execution.
278 Permission policy for this tool. Controls whether tool calls are auto-approved or require confirmation.
279279
280280 - `BetaManagedAgentsAlwaysAllowPolicy object`
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from line 305
305305
306306 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
307307
308 Permission policy for tool execution.
308 Permission policy for this tool. Controls whether tool calls are auto-approved or require confirmation.
309309
310310 - `BetaManagedAgentsAlwaysAllowPolicy object`
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from line 335
335335
336336 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
337337
338 Permission policy for tool execution.
338 Permission policy for this tool. Controls whether tool calls are auto-approved or require confirmation.
339339
340340 - `BetaManagedAgentsAlwaysAllowPolicy object`
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from line 379
379379
380380 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
381381
382 Permission policy for tool execution.
382 Permission policy for this tool. Controls whether tool calls are auto-approved or require confirmation.
383383
384384 - `BetaManagedAgentsAlwaysAllowPolicy object`
385385
from line 417
417417
418418 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
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420 Permission policy for tool execution.
420 Permission policy for this tool. Controls whether tool calls are auto-approved or require confirmation.
421421
422422 - `BetaManagedAgentsAlwaysAllowPolicy object`
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from line 463
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464464 - `default_config: optional BetaManagedAgentsAgentToolsetDefaultConfigParams or null`
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466 Default configuration for all tools in a toolset.
466 Default configuration applied to all tools in this set.
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468468 - `enabled: optional boolean or null`
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from line 471
471471
472472 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
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474 Permission policy for tool execution.
474 Default permission policy for tools. Controls whether tool calls are auto-approved or require confirmation.
475475
476476 - `BetaManagedAgentsAlwaysAllowPolicy object`
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from line 513
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514514 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
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516 Permission policy for tool execution.
516 Permission policy for this tool. Overrides the `default_config` setting.
517517
518518 - `BetaManagedAgentsAlwaysAllowPolicy object`
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from line 529
529529
530530 - `default_config: optional BetaManagedAgentsMCPToolsetDefaultConfigParams or null`
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532 Default configuration for all tools from an MCP server.
532 Default configuration for all tools from this server.
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534534 - `enabled: optional boolean or null`
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from line 537
537537
538538 - `permission_policy: optional BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy or BetaManagedAgentsAutoPolicy or null`
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540 Permission policy for tool execution.
540 Default permission policy for tools from this server.
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542542 - `BetaManagedAgentsAlwaysAllowPolicy object`
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from line 565
565565
566566 - `input_schema: BetaManagedAgentsCustomToolInputSchema`
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568 JSON Schema for custom tool input parameters.
568 JSON Schema defining the expected input parameters for the tool.
569569
570570 - `type: "object"`
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from line 581
581581
582582- `budget: optional BetaManagedAgentsBudgetLimit or null`
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584 A hard spend ceiling. The session stops issuing new model requests once the tracked list cost reaches `max_list_cost`.
584 Enforced spend ceiling for the session. Set an object to replace the budget of a session that was created with one, or `null` to remove it; omit to preserve. A budget cannot be added to a session created without one (rejected with reason `budget_create_only`), and a removed budget cannot be re-added. Allowed in any non-terminated status. Lowering `max_list_cost` to at or below the session's consumed list cost is rejected with reason `budget_not_raised`, and every model the session can run must have a public list price or the request is rejected with reason `model_not_budgetable`.
585585
586586 - `type: "limit"`
587587
588588 - `max_list_cost: BetaMonetaryAmount`
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590 A monetary amount in a specific currency.
590 Maximum list cost the session may accrue. List price is used regardless of any negotiated discount, so the cap fires at or before the actual charge.
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592592 - `amount: string`
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from line 649
649649
650650 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
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652 - `string`
653
652654 - `"claude-opus-5-5" or "claude-fable-5-1" or "claude-sonnet-5" or 12 more`
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654656 The model that will power your agent.
from line 717
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716718 High-performance model for agents and coding
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718 - `string`
719
720720 - `effort: optional BetaManagedAgentsEffortLow or BetaManagedAgentsEffortMedium or BetaManagedAgentsEffortHigh or 2 more`
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722 How hard Claude works on each turn. Sets `output_config.effort` on every Messages call the session makes.
722 How hard Claude works on each inference call. One of `low`, `medium`, `high`, `xhigh`, `max`. Always present; resolved to the per-model default at save time when not supplied.
723723
724724 - `BetaManagedAgentsEffortLow object`
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from line 757
757757
758758 - `speed: optional "standard" or "fast"`
759759
760 Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time.
760 Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Defaults to `standard`. Not all models support `fast`; invalid combinations are rejected at create time.
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762762 - `"standard"`
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from line 765
765765
766766 - `multiagent: BetaManagedAgentsSessionMultiagentCoordinator or null`
767767
768 Resolved coordinator topology with full agent definitions for each roster member.
768 Resolved multiagent orchestration configuration. Null when the agent is single-threaded.
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770770 - `type: "coordinator"`
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from line 1221
12211221
12221222 - `archived_at: string or null`
12231223
1224 A timestamp in RFC 3339 format
1224 When the session was archived. Null if not archived.
12251225
12261226 format: date-time
12271227
12281228 - `budget: BetaManagedAgentsBudgetLimit or null`
12291229
1230 A hard spend ceiling. The session stops issuing new model requests once the tracked list cost reaches `max_list_cost`.
1230 The session's enforced spend ceiling, or null when no budget is set.
12311231
12321232 - `type: "limit"`
12331233
12341234 - `max_list_cost: BetaMonetaryAmount`
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1236 A monetary amount in a specific currency.
1236 Maximum list cost the session may accrue. List price is used regardless of any negotiated discount, so the cap fires at or before the actual charge.
12371237
12381238 - `amount: string`
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from line 1261
12611261
12621262 - `completed_at: string or null`
12631263
1264 A timestamp in RFC 3339 format
1264 When the outcome reached a terminal result. Null while `pending`/`running`/`evaluating`.
12651265
12661266 format: date-time
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from line 1367
13671367
13681368 - `access: optional "read_write" or "read_only" or null`
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1370 Access mode for an attached memory store.
1370 Access mode for the mounted store. Defaults to `read_write`. `read_only` mounts the store as a read-only filesystem.
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13721372 - `"read_write"`
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from line 1393
13931393
13941394 - `stats: BetaManagedAgentsSessionStats`
13951395
1396 Timing statistics for a session.
1396 Timing statistics for the session.
13971397
13981398 - `active_seconds: optional number`
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from line 1437
14371437
14381438 - `usage: BetaManagedAgentsSessionUsage`
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1440 Cumulative token usage for a session across all turns.
1440 Cumulative token usage for the session.
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14421442 - `active_seconds: optional number`
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from line 1447
14471447
14481448 - `cache_creation: optional BetaManagedAgentsCacheCreationUsage`
14491449
1450 Prompt-cache creation token usage broken down by cache lifetime.
1450 Tokens used to create prompt cache entries, broken down by cache TTL.
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14521452 - `ephemeral_1h_input_tokens: optional number`
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from line 1475
14751475
14761476 - `list_cost: optional BetaMonetaryAmount or null`
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1478 A monetary amount in a specific currency.
1478 Cumulative list cost of the session across all turns, priced at public list rates. Absent until cost tracking is available for the session.
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14801480 - `output_tokens: optional number`
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from line 1485
14851485
14861486 - `server_tool_use: optional BetaManagedAgentsServerToolUsage or null`
14871487
1488 Cumulative count of server-executed tool invocations, broken down by tool.
1488 Cumulative server-executed tool usage across all turns. Absent until server-tool tracking is available for the session.
14891489
14901490 - `web_fetch_requests: optional number`
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