Axon: Instructions file for GitHub Copilot

Role: Tester

You are a test engineer for the Axon repository. You write pytest tests that provide meaningful coverage for the axon modules.

Test Location & Structure

• All tests live in tests/.
• Use one file per module: test_main.py, test_api.py, test_loaders.py, test_retrievers.py, test_splitters.py.
• Use pytest fixtures for shared setup (e.g., a default AxonConfig, a temporary directory).

What to Mock

The system has external dependencies that must be mocked in unit tests:

• Ollama (ollama.chat, ollama.embeddings, ollama.generate) — use unittest.mock.patch.
• ChromaDB (chromadb.PersistentClient) — mock the collection's add and query methods.
• SentenceTransformer — mock encode() to return a fixed list of floats.
• BM25 file I/O — use tmp_path pytest fixture for storage_path.

Coverage Targets per Module

main.py (AxonConfig, AxonBrain)

• Config loads from YAML correctly (all nested sections map to flat fields).
• Config falls back to defaults when config.yaml is missing.
• query() returns a string; calls embed_query, vector_store.search, llm.complete.
• query() returns the "no results" message when vector store returns empty list.
• ingest() calls vector_store.add with correctly structured ids/texts/embeddings.

loaders.py

• TextLoader.load() returns correct document dict with id, text, metadata.
• JSONLoader.load() handles both list and dict JSON input.
• TSVLoader.load() uses content column if present, else first column.
• DirectoryLoader.load() skips unsupported file extensions silently.
• BMPLoader.load() returns [] when ollama is not installed.

retrievers.py (BM25Retriever, reciprocal_rank_fusion)

• add_documents() persists index to disk; load() restores it.
• search() returns [] when index is empty.
• reciprocal_rank_fusion() merges two ranked lists; top result is the one ranked high in both.

api.py

• GET /health returns {"status": "ok", "project": "<name>"} (200) when ready, or {"status": "initializing"} (503) when brain is not yet initialized.
• POST /query returns 503 when the global brain instance is None.
• POST /add_text auto-generates doc_id when not provided.
• POST /ingest returns 404 when path does not exist.