Create Session changedapi/beta/sessions/create
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Lines+195added
Lines−4removed
From line
183
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First seen
14 Aug 2026
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Recorded edits18to this page, all time
The whole hunk
from line 183, old and new numbered
/
from line 183
183183
184184 Replacement model. Accepts the model string, e.g. `claude-opus-5`, or a `model_config` object. Omit to use the agent's model.
185185
186 - `BetaManagedAgentsModel = "claude-sonnet-5-5" or "claude-opus-5-5" or "claude-fable-5-1" or 13 more or string`
186 - `BetaManagedAgentsModel = "claude-haiku-5-5" or "claude-sonnet-5-5" or "claude-opus-5-5" or 14 more or string`
187187
188188 The model that will power your agent.
189189
190190 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
191191
192 - `"claude-haiku-5-5"`
193
194 Fastest model for high-volume, real-time tasks
195
192196 - `"claude-sonnet-5-5"`
193197
194198 Efficient model for coding and agents
from line 629
625629
626630 The server decides each tool call individually: it judges, from the tool, its input, and the session content so far, whether the call is safe to execute or high-risk, and evaluates it to allow when judged safe and to deny when judged high-risk. A call the server cannot reach a judgement on evaluates to ask.
627631
632 - `url_sources: optional BetaManagedAgentsWebFetchURLSourcesParams or null`
633
634 Which sources contribute URLs the tool may fetch. Omit to allow every source.
635
636 - `client_tool_results: optional BetaManagedAgentsWebFetchURLSourceToolFilterParams or null`
637
638 Which custom tools' results contribute URLs that may be fetched: "all" (the default), "none", or an only or except list. Each name in a list must be a custom tool in the same tools array.
639
640 - `BetaManagedAgentsWebFetchURLSourceShorthand = "all" or "none"`
641
642 String form of a url_sources value that has no field other than its type: "all" means {"type": "all"} and "none" means {"type": "none"}.
643
644 - `"all"`
645
646 - `"none"`
647
648 - `BetaManagedAgentsWebFetchURLSourceToolFilter = BetaManagedAgentsWebFetchURLSourceAll or BetaManagedAgentsWebFetchURLSourceNone or BetaManagedAgentsWebFetchURLSourceOnly or BetaManagedAgentsWebFetchURLSourceExcept`
649
650 Which tools' results contribute URLs that may be fetched.
651
652 - `BetaManagedAgentsWebFetchURLSourceAll object`
653
654 Every URL from this source may be fetched. This is the default.
655
656 - `type: "all"`
657
658 - `BetaManagedAgentsWebFetchURLSourceNone object`
659
660 This source contributes no URLs that may be fetched.
661
662 - `type: "none"`
663
664 - `BetaManagedAgentsWebFetchURLSourceOnly object`
665
666 Only the named tools' results contribute URLs that may be fetched.
667
668 - `type: "only"`
669
670 - `tools: array of BetaManagedAgentsWebFetchURLSourceToolReference`
671
672 The tools whose results contribute. Between 1 and 128 entries, each with a different name. An empty list is rejected; use "none" to allow no tool's results.
673
674 - `type: "tool_reference"`
675
676 Must be "tool_reference".
677
678 - `name: string`
679
680 Name of the tool. Compared exactly, so upper and lower case letters are different.
681
682 minLength: 1, maxLength: 128
683
684 - `BetaManagedAgentsWebFetchURLSourceExcept object`
685
686 Every tool's results contribute URLs that may be fetched, except the named tools' results.
687
688 - `type: "except"`
689
690 - `tools: array of BetaManagedAgentsWebFetchURLSourceToolReference`
691
692 The tools whose results do not contribute. Between 1 and 128 entries, each with a different name. An empty list is rejected; use "all" to leave out no tool's results.
693
694 - `type: "tool_reference"`
695
696 Must be "tool_reference".
697
698 - `name: string`
699
700 Name of the tool. Compared exactly, so upper and lower case letters are different.
701
702 minLength: 1, maxLength: 128
703
704 - `server_tool_results: optional BetaManagedAgentsWebFetchURLSourceToolFilterParams or null`
705
706 Which of the web_search and web_fetch tools' results contribute URLs that may be fetched: "all" (the default), "none", or an only or except list. Each name in a list must be "web_search" or "web_fetch".
707
708 - `user_input: optional BetaManagedAgentsWebFetchURLSourceUserInputParams or null`
709
710 Whether URLs in the text of user messages may be fetched: "all" (the default) or "none".
711
712 - `BetaManagedAgentsWebFetchURLSourceShorthand = "all" or "none"`
713
714 String form of a url_sources value that has no field other than its type: "all" means {"type": "all"} and "none" means {"type": "none"}.
715
716 - `BetaManagedAgentsWebFetchURLSourceUserInput = BetaManagedAgentsWebFetchURLSourceAll or BetaManagedAgentsWebFetchURLSourceNone`
717
718 Whether URLs in the text of user messages may be fetched.
719
720 - `BetaManagedAgentsWebFetchURLSourceAll object`
721
722 Every URL from this source may be fetched. This is the default.
723
724 - `BetaManagedAgentsWebFetchURLSourceNone object`
725
726 This source contributes no URLs that may be fetched.
727
628728 - `BetaManagedAgentsWebSearchToolConfigParams object`
629729
630730 Configuration override for the web_search tool.
from line 1289
11891289
11901290 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
11911291
1292 - `"claude-haiku-5-5"`
1293
1294 Fastest model for high-volume, real-time tasks
1295
11921296 - `"claude-sonnet-5-5"`
11931297
11941298 Efficient model for coding and agents
from line 1663
15591663
15601664 The server decides each tool call individually: it judges, from the tool, its input, and the session content so far, whether the call is safe to execute or high-risk, and evaluates it to allow when judged safe and to deny when judged high-risk. A call the server cannot reach a judgement on evaluates to ask.
15611665
1666 - `url_sources: BetaManagedAgentsWebFetchURLSources or null`
1667
1668 Which sources contribute URLs the tool may fetch, always in the object form. Null when not set, which allows every source.
1669
1670 - `client_tool_results: BetaManagedAgentsWebFetchURLSourceToolFilter or null`
1671
1672 Which custom tools' results contribute URLs that may be fetched. Null when not set, which allows every custom tool's results.
1673
1674 - `BetaManagedAgentsWebFetchURLSourceAll object`
1675
1676 Every URL from this source may be fetched. This is the default.
1677
1678 - `type: "all"`
1679
1680 - `BetaManagedAgentsWebFetchURLSourceNone object`
1681
1682 This source contributes no URLs that may be fetched.
1683
1684 - `type: "none"`
1685
1686 - `BetaManagedAgentsWebFetchURLSourceOnly object`
1687
1688 Only the named tools' results contribute URLs that may be fetched.
1689
1690 - `type: "only"`
1691
1692 - `tools: array of BetaManagedAgentsWebFetchURLSourceToolReference`
1693
1694 The tools whose results contribute. Between 1 and 128 entries, each with a different name. An empty list is rejected; use "none" to allow no tool's results.
1695
1696 - `type: "tool_reference"`
1697
1698 Must be "tool_reference".
1699
1700 - `name: string`
1701
1702 Name of the tool. Compared exactly, so upper and lower case letters are different.
1703
1704 minLength: 1, maxLength: 128
1705
1706 - `BetaManagedAgentsWebFetchURLSourceExcept object`
1707
1708 Every tool's results contribute URLs that may be fetched, except the named tools' results.
1709
1710 - `type: "except"`
1711
1712 - `tools: array of BetaManagedAgentsWebFetchURLSourceToolReference`
1713
1714 The tools whose results do not contribute. Between 1 and 128 entries, each with a different name. An empty list is rejected; use "all" to leave out no tool's results.
1715
1716 - `type: "tool_reference"`
1717
1718 Must be "tool_reference".
1719
1720 - `name: string`
1721
1722 Name of the tool. Compared exactly, so upper and lower case letters are different.
1723
1724 minLength: 1, maxLength: 128
1725
1726 - `server_tool_results: BetaManagedAgentsWebFetchURLSourceToolFilter or null`
1727
1728 Which of the web_search and web_fetch tools' results contribute URLs that may be fetched. Null when not set, which allows both.
1729
1730 - `user_input: BetaManagedAgentsWebFetchURLSourceUserInput or null`
1731
1732 Whether URLs in the text of user messages may be fetched. Null when not set, which allows them.
1733
1734 - `BetaManagedAgentsWebFetchURLSourceAll object`
1735
1736 Every URL from this source may be fetched. This is the default.
1737
1738 - `BetaManagedAgentsWebFetchURLSourceNone object`
1739
1740 This source contributes no URLs that may be fetched.
1741
15621742 - `allowed_domains: optional array of string`
15631743
15641744 - `blocked_domains: optional array of string`
from line 2238
20582238 -d '{
20592239 "agent": "agent_011CZkYpogX7uDKUyvBTophP",
20602240 "environment_id": "env_011CZkZ9X2dpNyB7HsEFoRfW",
2241 "initial_events": [
2242 {
2243 "content": [
2244 {
2245 "text": "Where is my order #1234?",
2246 "type": "text"
2247 }
2248 ],
2249 "type": "user.message"
2250 }
2251 ],
20612252 "title": "Order #1234 inquiry"
20622253 }'
20632254```
from line 2340
21492340 "version": "1"
21502341 },
21512342 {
2152 "skill_id": "skill_011CZkZFNu9hAbo3jZPRgTlx",
2343 "skill_id": "skill_011CZkZFNu9hAbo3jZPRgTmx",
21532344 "type": "custom",
21542345 "version": "2"
21552346 }
from line 2387
21962387 "description": "Produce a 2-page summary as summary.md",
21972388 "explanation": "All five sections present with inline citations.",
21982389 "iteration": 0,
2199 "outcome_id": "outc_011CZkZRSw2kEfs6ncTVljxP",
2390 "outcome_id": "outc_011CZkZRSw2kEfs6ncTVmjxP",
22002391 "result": "satisfied",
22012392 "type": "outcome_evaluation"
22022393 }
from line 2402
22112402 "updated_at": "2026-03-15T10:00:00Z"
22122403 },
22132404 {
2214 "id": "sesrsc_011CZkZCKr6eXyl0gWMOdQiu",
2405 "id": "sesrsc_011CZkZCKr6eXym1gWMPdQiu",
22152406 "created_at": "2026-03-15T10:00:00Z",
22162407 "mount_path": "/workspace/example-repo",
22172408 "type": "github_repository",
No line in this hunk matches that.