Fix Namespace gaps in HostedToolSearchTool#7500
Merged
Conversation
Adds a NamespaceDescription property to HostedToolSearchTool and threads it through OpenAIResponsesChatClient so the namespace wrapper sent to the OpenAI Responses API includes a 'description' field when one is provided. The description is conditionally emitted only when non-null/non-empty (the live service rejects empty strings). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…stances are supplied The OpenAI Responses API rejects requests with more than one tool_search tool in tools[] (HTTP 400: 'Only one tool_search tool is allowed in tools parameter'). When callers attach multiple HostedToolSearchTool instances - typically to scope different DeferredTools to different namespaces - AsCreateResponseOptions now emits only the first tool_search ResponseTool while still letting every instance contribute its Namespace/NamespaceDescription/DeferredTools to the namespace-grouping lookup. The dedupe is scoped to the request-building loop rather than the shared ToResponseTool helper so the public AsOpenAIResponseTool extension still converts every HostedToolSearchTool independently. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
rogerbarreto
approved these changes
May 1, 2026
Contributor
There was a problem hiding this comment.
Pull request overview
This PR updates the OpenAI Responses tool-search serialization to better support namespaced deferred tools, addressing service rejections due to missing namespace metadata and duplicated tool_search tool entries.
Changes:
- Added
HostedToolSearchTool.NamespaceDescription(experimental) to allow emitting a namespace description in the OpenAI payload. - Updated
OpenAIResponsesChatClientto (a) include namespace descriptions when constructing{"type":"namespace"}tools and (b) avoid sending multipletool_searchentries when multipleHostedToolSearchToolinstances are provided. - Expanded unit and integration tests to validate namespace descriptions and multi-namespace scenarios.
Reviewed changes
Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.
Show a summary per file
| File | Description |
|---|---|
| test/Libraries/Microsoft.Extensions.AI.OpenAI.Tests/OpenAIResponseClientTests.cs | Updates expected JSON to avoid duplicate tool_search entries; adds non-streaming coverage for namespace descriptions and merge behavior. |
| test/Libraries/Microsoft.Extensions.AI.OpenAI.Tests/OpenAIResponseClientIntegrationTests.cs | Adds live round-trip tests for tool search with one/two namespaces including descriptions. |
| test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Tools/HostedToolSearchToolTests.cs | Adds tests for NamespaceDescription default and round-trip behavior. |
| src/Libraries/Microsoft.Extensions.AI.OpenAI/OpenAIResponsesChatClient.cs | Adds namespace description emission, tool_search deduplication, and namespace description merge behavior. |
| src/Libraries/Microsoft.Extensions.AI.Abstractions/Tools/HostedToolSearchTool.cs | Introduces NamespaceDescription API with XML docs clarifying behavior. |
| src/Libraries/Microsoft.Extensions.AI.Abstractions/Microsoft.Extensions.AI.Abstractions.json | Updates API surface baseline for the new experimental property. |
…ol instances When several HostedToolSearchTool instances share a namespace name and only some supply a NamespaceDescription, the wrapper now uses the first non-empty description rather than first-writer-wins. ToolSearchLookup.Namespace is now a class with a settable Description so all entries in _namespacedToolNames sharing a namespace name reference the same instance and pick up later upgrades automatically; this also keeps namespaceGroups (keyed by reference equality) collapsed to one bucket per namespace name. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
jeffhandley
approved these changes
May 1, 2026
Contributor
There was a problem hiding this comment.
Pull request overview
Updates the OpenAI Responses chat client and tool-search abstractions to correctly support OpenAI “namespace” tool wrappers by allowing a namespace description to be sent, and to avoid emitting multiple tool_search entries when multiple HostedToolSearchTool instances are provided.
Changes:
- Add
NamespaceDescriptiontoHostedToolSearchTooland include it when emitting OpenAI{"type":"namespace"}tools. - Ensure only one
tool_searchtool is sent on the wire even if multipleHostedToolSearchToolinstances are configured. - Expand unit and integration test coverage for namespace descriptions and multi-namespace tool search scenarios.
Reviewed changes
Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.
Show a summary per file
| File | Description |
|---|---|
| src/Libraries/Microsoft.Extensions.AI.OpenAI/OpenAIResponsesChatClient.cs | Emits namespace tool description (when provided) and dedupes tool_search; tracks namespaces with name+description. |
| src/Libraries/Microsoft.Extensions.AI.Abstractions/Tools/HostedToolSearchTool.cs | Adds NamespaceDescription API surface with remarks. |
| src/Libraries/Microsoft.Extensions.AI.Abstractions/Microsoft.Extensions.AI.Abstractions.json | Adds API baseline entry for NamespaceDescription (Experimental). |
| test/Libraries/Microsoft.Extensions.AI.OpenAI.Tests/OpenAIResponseClientTests.cs | Updates expected JSON to include only one tool_search; adds tests for namespace description behaviors. |
| test/Libraries/Microsoft.Extensions.AI.OpenAI.Tests/OpenAIResponseClientIntegrationTests.cs | Adds live tests to validate namespace wrappers with descriptions round-trip with tool search enabled. |
| test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Tools/HostedToolSearchToolTests.cs | Adds unit tests for NamespaceDescription default/roundtrip. |
jeffhandley
pushed a commit
that referenced
this pull request
May 1, 2026
* Add HostedToolSearchTool.NamespaceDescription support Adds a NamespaceDescription property to HostedToolSearchTool and threads it through OpenAIResponsesChatClient so the namespace wrapper sent to the OpenAI Responses API includes a 'description' field when one is provided. The description is conditionally emitted only when non-null/non-empty (the live service rejects empty strings). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Emit a single tool_search entry when multiple HostedToolSearchTool instances are supplied The OpenAI Responses API rejects requests with more than one tool_search tool in tools[] (HTTP 400: 'Only one tool_search tool is allowed in tools parameter'). When callers attach multiple HostedToolSearchTool instances - typically to scope different DeferredTools to different namespaces - AsCreateResponseOptions now emits only the first tool_search ResponseTool while still letting every instance contribute its Namespace/NamespaceDescription/DeferredTools to the namespace-grouping lookup. The dedupe is scoped to the request-building loop rather than the shared ToResponseTool helper so the public AsOpenAIResponseTool extension still converts every HostedToolSearchTool independently. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Prefer first non-empty NamespaceDescription across HostedToolSearchTool instances When several HostedToolSearchTool instances share a namespace name and only some supply a NamespaceDescription, the wrapper now uses the first non-empty description rather than first-writer-wins. ToolSearchLookup.Namespace is now a class with a settable Description so all entries in _namespacedToolNames sharing a namespace name reference the same instance and pick up later upgrades automatically; this also keeps namespaceGroups (keyed by reference equality) collapsed to one bucket per namespace name. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> --------- Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Microsoft Reviewers: Open in CodeFlow