feat(autogen-ext): add Perplexity model client + search tool

[jliounis]

Summary

Adds two new Perplexity components to autogen-ext, mirroring the existing OpenAI / Anthropic / HTTP-tool patterns:

1. autogen_ext.models.perplexity.PerplexityChatCompletionClient

A thin wrapper around OpenAIChatCompletionClient targeting Perplexity's OpenAI-compatible chat completions endpoint at https://api.perplexity.ai. Reads PERPLEXITY_API_KEY (or the PPLX_API_KEY alias) from the environment when no api_key is passed. Ships a sensible default model_info block (function_calling, json_output, structured_output enabled; vision disabled) so users can wire the client up without supplying their own.

from autogen_ext.models.perplexity import PerplexityChatCompletionClient
client = PerplexityChatCompletionClient(model="sonar")

Pattern mirrors autogen_ext/models/openai/_openai_client.py's gemini/claude/llama base-URL shortcuts.

2. autogen_ext.tools.perplexity.PerplexitySearchTool

A BaseTool that calls POST https://api.perplexity.ai/search and returns structured ranked web results (title, url, snippet, optional date). Implements the standard AutoGen Component[...] round-trip via PerplexitySearchToolConfig (mirroring HttpTool).

Args (PerplexitySearchToolArgs):

• query: str
• max_results: int (default 5, capped at 20)
• search_domain_filter: list[str] | None — allow- or deny-list; prefix a domain with - to exclude. Do not mix allow and deny in a single call.
• search_recency_filter: Literal["hour","day","week","month","year"] | None

Tool description deliberately does not reference Sonar models — surfaces the Search API as the product, per the linked Perplexity docs.

Other changes

• New [perplexity] extra in python/packages/autogen-ext/pyproject.toml. Install with pip install -U "autogen-ext[perplexity]".
• New tutorial page python/docs/src/user-guide/agentchat-user-guide/tutorial/perplexity.md (registered in tutorial/index.md and the parent toctree).

Testing

13 mocked unit tests, no live HTTP:

• tests/models/test_perplexity_model_client.py (6 tests): missing-key error, env-var pickup, PPLX_API_KEY alias fallback, explicit-key precedence, custom base URL, default model_info shape.
• tests/tools/test_perplexity_search_tool.py (7 tests): missing-key error, structured-result parsing, request-payload assertions (URL, headers, body), env-var alias, HTTP error propagation, tool metadata (no Sonar mention), dump_component / load_component round-trip.

Run them with:

cd python
uv sync --no-dev --package autogen-ext --extra perplexity
uv run --no-sync pytest packages/autogen-ext/tests/ -k perplexity -v

uv run --no-sync ruff check and uv run --no-sync mypy are clean on the new files.

References

• Perplexity Agent API quickstart
• Perplexity Search API quickstart
• Search API reference

[jliounis]

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[jliounis]

@microsoft-github-policy-service agree company="Perplexity AI"

[jliounis]

@microsoft-github-policy-service agree company="Perplexity AI"

[jliounis]

Added the Perplexity attribution header (X-Pplx-Integration: autogen/<autogen-ext version>) to both the chat completion client and search tool request paths.

Validation: .venv/bin/python -m pytest python/packages/autogen-ext/tests/models/test_perplexity_model_client.py python/packages/autogen-ext/tests/tools/test_perplexity_search_tool.py (13 passed).

Noted that the PR is still waiting on Microsoft CLA; I did not block on that.

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