diff --git a/docs/configuration.md b/docs/configuration.md
index 58210bea..4cb9973c 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -98,16 +98,28 @@ providers:
     qa_base_url: ""
     research_base_url: ""
 
-  api_keys:
-    voyage: ""
-    openai: ""
-    anthropic: ""
-    cohere: ""
-
 a2a:
   max_contexts: 1000
 ```
 
+## API Keys
+
+API keys are configured through **environment variables**, not in the YAML file.
+
+```bash
+# OpenAI
+export OPENAI_API_KEY=your-key-here
+
+# Anthropic
+export ANTHROPIC_API_KEY=your-key-here
+
+# Voyage AI
+export VOYAGE_API_KEY=your-key-here
+
+# Cohere
+export CO_API_KEY=your-key-here
+```
+
 ## File Monitoring
 
 Set directories to monitor for automatic indexing:
@@ -145,10 +157,12 @@ embeddings:
   provider: voyageai
   model: voyage-3.5
   vector_dim: 1024
+```
 
-providers:
-  api_keys:
-    voyage: your-api-key
+Set your API key via environment variable:
+
+```bash
+export VOYAGE_API_KEY=your-api-key
 ```
 
 ### OpenAI
@@ -160,10 +174,12 @@ embeddings:
   provider: openai
   model: text-embedding-3-small  # or text-embedding-3-large
   vector_dim: 1536
+```
 
-providers:
-  api_keys:
-    openai: your-api-key
+Set your API key via environment variable:
+
+```bash
+export OPENAI_API_KEY=your-api-key
 ```
 
 ### vLLM
@@ -207,10 +223,12 @@ OpenAI QA is included in the default installation:
 qa:
   provider: openai
   model: gpt-4o-mini  # or gpt-4, gpt-3.5-turbo, etc.
+```
 
-providers:
-  api_keys:
-    openai: your-api-key
+Set your API key via environment variable:
+
+```bash
+export OPENAI_API_KEY=your-api-key
 ```
 
 ### Anthropic
@@ -221,10 +239,12 @@ Anthropic QA is included in the default installation:
 qa:
   provider: anthropic
   model: claude-3-5-haiku-20241022  # or claude-3-5-sonnet-20241022, etc.
+```
 
-providers:
-  api_keys:
-    anthropic: your-api-key
+Set your API key via environment variable:
+
+```bash
+export ANTHROPIC_API_KEY=your-api-key
 ```
 
 ### vLLM
@@ -296,10 +316,12 @@ Cohere reranking is included in the default installation:
 reranking:
   provider: cohere
   model: rerank-v3.5
+```
 
-providers:
-  api_keys:
-    cohere: your-api-key
+Set your API key via environment variable:
+
+```bash
+export CO_API_KEY=your-api-key
 ```
 
 ### vLLM
diff --git a/src/haiku/rag/config/__init__.py b/src/haiku/rag/config/__init__.py
index 7af9c6f2..e0299a6f 100644
--- a/src/haiku/rag/config/__init__.py
+++ b/src/haiku/rag/config/__init__.py
@@ -9,7 +9,6 @@ from haiku.rag.config.loader import (
 )
 from haiku.rag.config.models import (
     A2AConfig,
-    APIKeysConfig,
     AppConfig,
     EmbeddingsConfig,
     LanceDBConfig,
@@ -35,7 +34,6 @@ __all__ = [
     "ProcessingConfig",
     "OllamaConfig",
     "VLLMConfig",
-    "APIKeysConfig",
     "ProvidersConfig",
     "A2AConfig",
     "find_config_file",
@@ -54,14 +52,3 @@ else:
 
 # Check for deprecated .env file
 check_for_deprecated_env()
-
-# Export API keys to os.environ for provider libraries
-if Config.providers.api_keys.openai:
-    os.environ["OPENAI_API_KEY"] = Config.providers.api_keys.openai
-if Config.providers.api_keys.voyage:
-    os.environ["VOYAGE_API_KEY"] = Config.providers.api_keys.voyage
-if Config.providers.api_keys.anthropic:
-    os.environ["ANTHROPIC_API_KEY"] = Config.providers.api_keys.anthropic
-if Config.providers.api_keys.cohere:
-    # Cohere SDK expects CO_API_KEY (not COHERE_API_KEY)
-    os.environ["CO_API_KEY"] = Config.providers.api_keys.cohere
diff --git a/src/haiku/rag/config/loader.py b/src/haiku/rag/config/loader.py
index 147bb542..c2bf1240 100644
--- a/src/haiku/rag/config/loader.py
+++ b/src/haiku/rag/config/loader.py
@@ -90,7 +90,6 @@ def generate_default_config() -> dict:
                 "qa_base_url": "",
                 "research_base_url": "",
             },
-            "api_keys": {"voyage": "", "openai": "", "anthropic": "", "cohere": ""},
         },
         "a2a": {"max_contexts": 1000},
     }
@@ -126,10 +125,6 @@ def load_config_from_env() -> dict:
         "VLLM_RERANK_BASE_URL": ("providers", "vllm", "rerank_base_url"),
         "VLLM_QA_BASE_URL": ("providers", "vllm", "qa_base_url"),
         "VLLM_RESEARCH_BASE_URL": ("providers", "vllm", "research_base_url"),
-        "VOYAGE_API_KEY": ("providers", "api_keys", "voyage"),
-        "OPENAI_API_KEY": ("providers", "api_keys", "openai"),
-        "ANTHROPIC_API_KEY": ("providers", "api_keys", "anthropic"),
-        "COHERE_API_KEY": ("providers", "api_keys", "cohere"),
         "A2A_MAX_CONTEXTS": ("a2a", "max_contexts"),
     }
 
diff --git a/src/haiku/rag/config/models.py b/src/haiku/rag/config/models.py
index 51bb55a5..3fdd6bc8 100644
--- a/src/haiku/rag/config/models.py
+++ b/src/haiku/rag/config/models.py
@@ -56,17 +56,9 @@ class VLLMConfig(BaseModel):
     research_base_url: str = ""
 
 
-class APIKeysConfig(BaseModel):
-    voyage: str = ""
-    openai: str = ""
-    anthropic: str = ""
-    cohere: str = ""
-
-
 class ProvidersConfig(BaseModel):
     ollama: OllamaConfig = Field(default_factory=OllamaConfig)
     vllm: VLLMConfig = Field(default_factory=VLLMConfig)
-    api_keys: APIKeysConfig = Field(default_factory=APIKeysConfig)
 
 
 class A2AConfig(BaseModel):
diff --git a/src/haiku/rag/reranking/cohere.py b/src/haiku/rag/reranking/cohere.py
index 69f4f7d6..439cbca2 100644
--- a/src/haiku/rag/reranking/cohere.py
+++ b/src/haiku/rag/reranking/cohere.py
@@ -1,4 +1,3 @@
-from haiku.rag.config import Config
 from haiku.rag.reranking.base import RerankerBase
 from haiku.rag.store.models.chunk import Chunk
 
@@ -12,7 +11,8 @@ except ImportError as e:
 
 class CohereReranker(RerankerBase):
     def __init__(self):
-        self._client = cohere.ClientV2(api_key=Config.providers.api_keys.cohere)
+        # Cohere SDK reads CO_API_KEY from environment by default
+        self._client = cohere.ClientV2()
 
     async def rerank(
         self, query: str, chunks: list[Chunk], top_n: int = 10
diff --git a/tests/test_config_loader.py b/tests/test_config_loader.py
index a2b0869f..991d1628 100644
--- a/tests/test_config_loader.py
+++ b/tests/test_config_loader.py
@@ -112,7 +112,6 @@ def test_load_config_from_env(monkeypatch):
     monkeypatch.setenv("EMBEDDINGS_VECTOR_DIM", "1536")
     monkeypatch.setenv("QA_PROVIDER", "anthropic")
     monkeypatch.setenv("QA_MODEL", "claude-3-haiku")
-    monkeypatch.setenv("OPENAI_API_KEY", "test-key")
 
     config = load_config_from_env()
 
@@ -122,7 +121,6 @@ def test_load_config_from_env(monkeypatch):
     assert config["embeddings"]["vector_dim"] == "1536"
     assert config["qa"]["provider"] == "anthropic"
     assert config["qa"]["model"] == "claude-3-haiku"
-    assert config["providers"]["api_keys"]["openai"] == "test-key"
 
 
 def test_load_config_from_env_empty():
diff --git a/tests/test_embedder.py b/tests/test_embedder.py
index 1391fe35..4ef9e7bc 100644
--- a/tests/test_embedder.py
+++ b/tests/test_embedder.py
@@ -1,3 +1,5 @@
+import os
+
 import numpy as np
 import pytest
 
@@ -6,8 +8,8 @@ from haiku.rag.embeddings.ollama import Embedder as OllamaEmbedder
 from haiku.rag.embeddings.openai import Embedder as OpenAIEmbedder
 from haiku.rag.embeddings.vllm import Embedder as VLLMEmbedder
 
-OPENAI_AVAILABLE = bool(Config.providers.api_keys.openai)
-VOYAGEAI_AVAILABLE = bool(Config.providers.api_keys.voyage)
+OPENAI_AVAILABLE = bool(os.getenv("OPENAI_API_KEY"))
+VOYAGEAI_AVAILABLE = bool(os.getenv("VOYAGE_API_KEY"))
 VLLM_EMBEDDINGS_AVAILABLE = bool(Config.providers.vllm.embeddings_base_url)
 
 
diff --git a/tests/test_qa.py b/tests/test_qa.py
index 2bcf20a5..16c47971 100644
--- a/tests/test_qa.py
+++ b/tests/test_qa.py
@@ -1,3 +1,5 @@
+import os
+
 import pytest
 from datasets import Dataset
 
@@ -6,8 +8,8 @@ from haiku.rag.client import HaikuRAG
 from haiku.rag.config import Config
 from haiku.rag.qa.agent import QuestionAnswerAgent
 
-OPENAI_AVAILABLE = bool(Config.providers.api_keys.openai)
-ANTHROPIC_AVAILABLE = bool(Config.providers.api_keys.anthropic)
+OPENAI_AVAILABLE = bool(os.getenv("OPENAI_API_KEY"))
+ANTHROPIC_AVAILABLE = bool(os.getenv("ANTHROPIC_API_KEY"))
 VLLM_QA_AVAILABLE = bool(Config.providers.vllm.qa_base_url)
 
 
diff --git a/tests/test_reranker.py b/tests/test_reranker.py
index bc98b5b6..cc93f584 100644
--- a/tests/test_reranker.py
+++ b/tests/test_reranker.py
@@ -1,3 +1,5 @@
+import os
+
 import pytest
 
 from haiku.rag.config import Config
@@ -5,7 +7,7 @@ from haiku.rag.reranking.base import RerankerBase
 from haiku.rag.reranking.vllm import VLLMReranker
 from haiku.rag.store.models.chunk import Chunk
 
-COHERE_AVAILABLE = bool(Config.providers.api_keys.cohere)
+COHERE_AVAILABLE = bool(os.getenv("CO_API_KEY"))
 VLLM_RERANK_AVAILABLE = bool(Config.providers.vllm.rerank_base_url)
 
 chunks = [