Python: [BREAKING] parameter naming and other fixes

[eavanvalkenburg]

Motivation and Context

Made the use of model_id consistent across agents, chat_clients and types, in some places model was used, that is now always model_id.
Also made some improvements in parameter names on the agents for the additional options passed to the chat client.
Improved the parsing of additional_properties for several clients.
Improved the handling of Responses Reasoning content, and improved sample
Also removed to_provider_settings from ChatOptions, as it was not used, and to_dict does a similar thing.
Added handling of type to exclude from to_dict.

Closes #1245 #1246

Description

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines
• All unit tests pass, and I have added new tests where possible
• Is this a breaking change? If yes, add "[BREAKING]" prefix to the title of the PR.

[Copilot]

Pull Request Overview

This PR standardizes parameter naming across the Agent Framework by making model_id the consistent parameter name instead of the previously mixed usage of model and model_id. Additionally, it improves parameter handling for additional chat options and enhances reasoning content processing in OpenAI clients.

• Renamed model parameter to model_id across agents, chat clients, and type definitions for consistency
• Renamed request_kwargs to additional_chat_options in agent constructors for clarity
• Improved parsing and handling of additional properties in OpenAI chat and responses clients

Reviewed Changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
python/samples/getting_started/agents/openai/openai_responses_client_reasoning.py	Updated sample to use gpt-5 model and improved reasoning content handling with proper additional_chat_options usage
python/packages/devui/agent_framework_devui/models/_discovery_models.py	Changed model field to model_id in EntityInfo model
python/packages/devui/agent_framework_devui/_session.py	Updated parameter name from model to model_id in session management
python/packages/devui/agent_framework_devui/_discovery.py	Updated model parameter references to use model_id
python/packages/core/tests/openai/test_openai_chat_client_base.py	Added test for additional_properties handling and cleaned up test formatting
python/packages/core/tests/core/test_types.py	Removed unused imports, updated exception handling to use ContentError, and removed redundant test cases
python/packages/core/tests/core/test_observability.py	Updated test calls to use model_id parameter instead of model
python/packages/core/agent_framework/openai/_responses_client.py	Enhanced additional properties parsing and added summary content handling for reasoning responses
python/packages/core/agent_framework/openai/_chat_client.py	Improved options preparation with better additional properties handling
python/packages/core/agent_framework/observability.py	Updated observability tracking to use model_id parameter consistently
python/packages/core/agent_framework/exceptions.py	Added new ContentError exception class
python/packages/core/agent_framework/azure/_shared.py	Removed unused parameter documentation
python/packages/core/agent_framework/_types.py	Major refactoring of content parsing, ChatOptions, and parameter handling with improved error handling
python/packages/core/agent_framework/_serialization.py	Enhanced serialization to conditionally exclude type field
python/packages/core/agent_framework/_middleware.py	Updated middleware to use model_id instead of model
python/packages/core/agent_framework/_clients.py	Comprehensive parameter renaming from model to model_id and improved documentation
python/packages/core/agent_framework/_agents.py	Updated ChatAgent to use additional_chat_options instead of request_kwargs and improved parameter handling
python/packages/azure-ai/agent_framework_azure_ai/_chat_client.py	Updated Azure AI client to use model_id parameter and added ToolDefinition case handling

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[markwallace-microsoft]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
packages/azure-ai/agent_framework_azure_ai
_chat_client.py	362	67	81%	235, 240, 262–265, 269–270, 272, 346, 418, 487–488, 490–491, 499, 511–513, 517–519, 527–530, 540, 548–553, 560, 568–569, 577–578, 583–584, 588–595, 600–601, 609, 615, 623–625, 628, 683, 712–714, 717–718, 733, 738, 777–778, 911
packages/core/agent_framework
_agents.py	270	75	72%	290, 349–351, 397, 445, 463, 621, 684–687, 704, 714, 792–795, 797, 800–802, 920–923, 925, 928–930, 1012, 1017, 1047, 1052–1055, 1057, 1059, 1061, 1064–1069, 1071–1072, 1075, 1077, 1087–1088, 1090–1091, 1095, 1097–1098, 1106–1110, 1118–1119, 1121, 1123–1124, 1126, 1128, 1130, 1162, 1203–1204, 1206, 1219
_clients.py	115	15	86%	235, 293, 404, 423–424, 469–472, 516, 704, 708, 747, 835, 837
_middleware.py	396	9	97%	797, 813, 860–861, 1064–1065, 1110, 1259, 1472
_serialization.py	97	15	84%	185, 195–196, 201, 256, 260, 274, 276–280, 298–299, 312
_types.py	877	99	88%	130–131, 149–150, 287, 289, 296, 315, 355, 401–402, 438, 588, 702–703, 705, 730, 737, 754–756, 829, 834–835, 837, 844–845, 847, 869, 876, 879–881, 886–887, 893–895, 1016, 1142, 1323, 1327, 1329, 1573–1575, 1581–1582, 1750, 1826, 1831, 1881, 1886, 1890, 1894, 2101–2105, 2115, 2120, 2401, 2579, 2665–2667, 2690, 2717, 2740, 2748–2752, 2856, 2926, 2930, 2938, 2942–2944, 3045–3047, 3049–3051, 3054, 3058, 3061, 3066, 3120–3122, 3137, 3153, 3181, 3188
exceptions.py	48	0	100%
observability.py	603	109	81%	237, 263–265, 267, 269–273, 281, 287–292, 315–317, 319–320, 326, 410, 420, 442, 448, 467–469, 477–479, 502–504, 514–516, 649, 651, 738–742, 745–749, 758–761, 771–774, 776, 863–866, 1041, 1189–1191, 1346, 1353, 1355, 1357, 1359, 1361, 1363, 1365, 1367, 1369, 1371, 1375–1377, 1379, 1389, 1417–1418, 1428, 1431–1434, 1448, 1453–1455, 1457–1460, 1462–1463, 1467, 1470, 1490, 1528, 1544, 1548, 1672, 1674
packages/core/agent_framework/azure
_responses_client.py	28	2	92%	100, 123
_shared.py	79	7	91%	135–136, 199, 202, 215, 217, 227
packages/core/agent_framework/openai
_chat_client.py	235	44	81%	106–107, 111, 129, 139–140, 142, 153, 160, 164, 166–169, 178, 224, 255, 260–274, 281–283, 360, 363, 365, 367, 390–391, 397, 413, 455
_responses_client.py	409	68	83%	141–142, 145–146, 152–153, 156, 163, 195, 204, 216, 246, 274–275, 298, 390, 467, 472, 476–478, 498, 501, 516–517, 521–523, 571, 591–592, 605–606, 622–623, 661, 663, 707, 711, 713, 722, 724, 733–734, 747, 749, 822–828, 845–850, 869, 887, 897, 899, 917–918, 920–922
TOTAL	10308	1736	83%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
1254	98 💤	0 ❌	0 🔥	30.008s ⏱️