diff --git a/blockrun_llm/anthropic_client.py b/blockrun_llm/anthropic_client.py
index dbbf523..b0b418b 100644
--- a/blockrun_llm/anthropic_client.py
+++ b/blockrun_llm/anthropic_client.py
@@ -29,6 +29,11 @@
 
 load_dotenv()
 
+# Default chat HTTP timeout (seconds). Was 120; reasoning models (opus-4.8) think
+# 200–300s+, which the old default cut off mid-generation. Override via the
+# BLOCKRUN_CHAT_TIMEOUT env var. Mirrors client.py / solana_client.py.
+DEFAULT_CHAT_TIMEOUT = float(os.environ.get("BLOCKRUN_CHAT_TIMEOUT", "600"))
+
 
 class _BlockRunX402Transport(httpx.BaseTransport):
     """Custom httpx transport that intercepts 402 responses and signs x402 payments."""
@@ -123,7 +128,7 @@ def __init__(
         self,
         private_key: Optional[str] = None,
         api_url: Optional[str] = None,
-        timeout: float = 120.0,
+        timeout: float = DEFAULT_CHAT_TIMEOUT,
         **kwargs,
     ):
         """
@@ -133,7 +138,8 @@ def __init__(
             private_key: Base chain wallet private key (or set BLOCKRUN_WALLET_KEY env var).
                          Key is used for LOCAL signing only — never transmitted.
             api_url: BlockRun API endpoint (default: https://blockrun.ai/api).
-            timeout: Request timeout in seconds (default: 120).
+            timeout: Request timeout in seconds (default: 600, override via
+                     BLOCKRUN_CHAT_TIMEOUT env). Reasoning models need 200–300s+.
             **kwargs: Additional keyword arguments passed to anthropic.Anthropic.
 
         Raises:
diff --git a/blockrun_llm/client.py b/blockrun_llm/client.py
index d158c2d..621b723 100644
--- a/blockrun_llm/client.py
+++ b/blockrun_llm/client.py
@@ -239,7 +239,7 @@ def __init__(
             private_key: Base chain wallet private key (or set BLOCKRUN_WALLET_KEY env var)
                          NOTE: Key is used for LOCAL signing only - never transmitted
             api_url: API endpoint URL (default: https://blockrun.ai/api)
-            timeout: Request timeout in seconds (default: 120). Used for regular chat requests.
+            timeout: Request timeout in seconds (default: 600, override via BLOCKRUN_CHAT_TIMEOUT env). Used for regular chat requests.
             search_timeout: Timeout for xAI Live Search requests (default: 300 = 5 minutes).
                            Live Search can be slow as it searches X, web, and news sources.
                            Auto-detected when search_parameters or search=True is passed.
@@ -2202,7 +2202,7 @@ def __init__(
         Args:
             private_key: Base chain wallet private key (or set BLOCKRUN_WALLET_KEY env var)
             api_url: API endpoint URL (default: https://blockrun.ai/api)
-            timeout: Request timeout in seconds (default: 120). Used for regular chat requests.
+            timeout: Request timeout in seconds (default: 600, override via BLOCKRUN_CHAT_TIMEOUT env). Used for regular chat requests.
             search_timeout: Timeout for xAI Live Search requests (default: 300 = 5 minutes).
                            Auto-detected when search_parameters or search=True is passed.
             transaction_log: Same opt-in per-call log as ``LLMClient``. ``True`` →
diff --git a/blockrun_llm/solana_client.py b/blockrun_llm/solana_client.py
index 66fdd47..0992de1 100644
--- a/blockrun_llm/solana_client.py
+++ b/blockrun_llm/solana_client.py
@@ -86,7 +86,9 @@ def _create_signer(private_key: str) -> KeypairSigner:
 #
 # Public callers can also override per-call via ``timeout=`` on
 # ``chat_completion`` / ``image`` / ``image_edit`` / ``search``.
-DEFAULT_CHAT_TIMEOUT = float(os.environ.get("BLOCKRUN_CHAT_TIMEOUT", "600"))  # was 120; reasoning models need 200–300s+
+DEFAULT_CHAT_TIMEOUT = float(
+    os.environ.get("BLOCKRUN_CHAT_TIMEOUT", "600")
+)  # was 120; reasoning models need 200–300s+
 DEFAULT_IMAGE_TIMEOUT = 200.0
 DEFAULT_SEARCH_TIMEOUT = 300.0
 DEFAULT_FAST_TIMEOUT = 30.0  # pyth / x_user_info / quick lookups