g3fi+7dZddlmZddlZddlZddlZddlmZddlm Z ddl m Z m Z m Z mZmZddlmZerddlmZmZdd lmZdd lmZdd lmZGd d eZy)z!Tool retry middleware for agents.) annotationsN) TYPE_CHECKING) ToolMessage) OnFailureRetryOncalculate_delayshould_retry_exceptionvalidate_retry_params)AgentMiddleware) AwaitableCallable)Command)ToolCallRequest)BaseToolc eZdZdZddefdddddd  dfd Zdd Zdd Z dd Z ddZ ddZ xZ S)ToolRetryMiddlewarea Middleware that automatically retries failed tool calls with configurable backoff. Supports retrying on specific exceptions and exponential backoff. Examples: !!! example "Basic usage with default settings (2 retries, exponential backoff)" ```python from langchain.agents import create_agent from langchain.agents.middleware import ToolRetryMiddleware agent = create_agent(model, tools=[search_tool], middleware=[ToolRetryMiddleware()]) ``` !!! example "Retry specific exceptions only" ```python from requests.exceptions import RequestException, Timeout retry = ToolRetryMiddleware( max_retries=4, retry_on=(RequestException, Timeout), backoff_factor=1.5, ) ``` !!! example "Custom exception filtering" ```python from requests.exceptions import HTTPError def should_retry(exc: Exception) -> bool: # Only retry on 5xx errors if isinstance(exc, HTTPError): return 500 <= exc.status_code < 600 return False retry = ToolRetryMiddleware( max_retries=3, retry_on=should_retry, ) ``` !!! example "Apply to specific tools with custom error handling" ```python def format_error(exc: Exception) -> str: return "Database temporarily unavailable. Please try again later." retry = ToolRetryMiddleware( max_retries=4, tools=["search_database"], on_failure=format_error, ) ``` !!! example "Apply to specific tools using `BaseTool` instances" ```python from langchain_core.tools import tool @tool def search_database(query: str) -> str: '''Search the database.''' return results retry = ToolRetryMiddleware( max_retries=4, tools=[search_database], # Pass BaseTool instance ) ``` !!! example "Constant backoff (no exponential growth)" ```python retry = ToolRetryMiddleware( max_retries=5, backoff_factor=0.0, # No exponential growth initial_delay=2.0, # Always wait 2 seconds ) ``` !!! example "Raise exception on failure" ```python retry = ToolRetryMiddleware( max_retries=2, on_failure="error", # Re-raise exception instead of returning message ) ``` Ncontinueg@g?gN@T) max_retriestoolsretry_on on_failurebackoff_factor initial_delay max_delayjitterct |t|||||dk(r!d} tj| t dd}n%|dk(r d} tj| t dd}||_||2|D cgc] } t| ts | jn| "c} |_ nd |_ g|_ ||_ ||_ ||_||_||_||_y cc} w) uvInitialize `ToolRetryMiddleware`. Args: max_retries: Maximum number of retry attempts after the initial call. Must be `>= 0`. tools: Optional list of tools or tool names to apply retry logic to. Can be a list of `BaseTool` instances or tool name strings. If `None`, applies to all tools. retry_on: Either a tuple of exception types to retry on, or a callable that takes an exception and returns `True` if it should be retried. Default is to retry on all exceptions. on_failure: Behavior when all retries are exhausted. Options: - `'continue'`: Return a `ToolMessage` with error details, allowing the LLM to handle the failure and potentially recover. - `'error'`: Re-raise the exception, stopping agent execution. - **Custom callable:** Function that takes the exception and returns a string for the `ToolMessage` content, allowing custom error formatting. **Deprecated values** (for backwards compatibility): - `'return_message'`: Use `'continue'` instead. - `'raise'`: Use `'error'` instead. backoff_factor: Multiplier for exponential backoff. Each retry waits `initial_delay * (backoff_factor ** retry_number)` seconds. Set to `0.0` for constant delay. initial_delay: Initial delay in seconds before first retry. max_delay: Maximum delay in seconds between retries. Caps exponential backoff growth. jitter: Whether to add random jitter (`±25%`) to delay to avoid thundering herd. Raises: ValueError: If `max_retries < 0` or delays are negative. raisezion_failure='raise' is deprecated and will be removed in a future version. Use on_failure='error' instead.r) stacklevelerrorreturn_messagezuon_failure='return_message' is deprecated and will be removed in a future version. Use on_failure='continue' instead.rN)super__init__r warningswarnDeprecationWarningr isinstancestrname _tool_filterrrrrrrr) selfrrrrrrrrmsgtool __class__s d/var/www/auto_recruiter/arenv/lib/python3.12/site-packages/langchain/agents/middleware/tool_retry.pyr#zToolRetryMiddleware.__init__sr  k=)^T  2  MM#1a @ J + +J  MM#1a @#J&  ^c dVZ*T32GT!Q dD  $D    $,*" !es8%Cc8|jy||jvS)zCheck if retry logic should apply to this tool. Args: tool_name: Name of the tool being called. Returns: `True` if retry logic should apply, `False` otherwise. T)r*)r+ tool_names r/_should_retry_toolz&ToolRetryMiddleware._should_retry_tools$    $D----c xt|j}t|}|dk(rdnd}d|d|d|d|d|d S) a6Format the failure message when retries are exhausted. Args: tool_name: Name of the tool that failed. exc: The exception that caused the failure. attempts_made: Number of attempts actually made. Returns: Formatted error message string. attemptattemptszTool 'z' failed after  z with z: z. Please try again.)type__name__r()r+r1exc attempts_madeexc_typeexc_msg attempt_words r/_format_failure_messagez+ToolRetryMiddleware._format_failure_messages[9%%c($1Q$6yJ YK}oQ|nM:Ry(; = r3c|jdk(r|t|jr|j|}n|j|||}t|||dS)aHandle failure when all retries are exhausted. Args: tool_name: Name of the tool that failed. tool_call_id: ID of the tool call (may be `None`). exc: The exception that caused the failure. attempts_made: Number of attempts actually made. Returns: `ToolMessage` with error details. Raises: Exception: If `on_failure` is `'error'`, re-raises the exception. r )content tool_call_idr)status)rcallabler@r)r+r1rCr;r<rBs r/_handle_failurez#ToolRetryMiddleware._handle_failures\" ??g %I DOO $ooc*G229c=QG%   r3c |jr|jjn|jd}|j|s||S|jd}t |j dzD] } ||cSd} t#| #t $r}|dz}t||js|j||||cYd}~cS||j krSt||j|j|j|j}|dkDr1tj |n|j||||cYd}~cSYd}~d}~wwxYw)a<Intercept tool execution and retry on failure. Args: request: Tool call request with call dict, `BaseTool`, state, and runtime. handler: Callable to execute the tool (can be called multiple times). Returns: `ToolMessage` or `Command` (the final result). r)idr5Nrrrrr2Unexpected: retry loop completed without returning)r-r) tool_callr2ranger Exceptionr rrFrrrrrtimesleep RuntimeError r+requesthandlerr1rCr6r;r<delayr,s r/wrap_tool_callz"ToolRetryMiddleware.wrap_tool_callsH*1GLL%%7;L;LV;T &&y17# #((. T--12 ]G ]w'' ]:C37 ] '! .c4==A// <m\\T---+'+':':&*&8&8"&..#{{ Eqy 5) // <m\\/ ]s+6B E.EE A5EEEc K|jr|jjn|jd}|j|s||d{S|jd}t |j dzD]} ||d{cSd} t#| 7O7#t $r}|dz}t||js|j||||cYd}~cS||j kr\t||j|j|j|j}|dkDr:tj |d{7n|j||||cYd}~cSYd}~d}~wwxYww)ajIntercept and control async tool execution with retry logic. Args: request: Tool call request with call `dict`, `BaseTool`, state, and runtime. handler: Async callable to execute the tool and returns `ToolMessage` or `Command`. Returns: `ToolMessage` or `Command` (the final result). r)NrHr5rIrrJ)r-r)rKr2rLrrMr rrFrrrrrasynciorOrPrQs r/awrap_tool_callz#ToolRetryMiddleware.awrap_tool_callVsa*1GLL%%7;L;LV;T &&y1 )) )((. T--12 ]G ]$W--- ]:C3G*. ] '! .c4==A// <m\\T---+'+':':&*&8&8"&..#{{ Eqy%mmE222 // <m\\/ ]ssAE6B .E6 B$ B" B$E6"B$$ E3-.E.E3E6#A$E.E E.!E3" E6.E33E6)rintrzlist[BaseTool | str] | NonerrrrrfloatrrZrrZrboolreturnNone)r1r(r\r[)r1r(r;rMr<rYr\r() r1r(rCz str | Noner;rMr<rYr\r)rRrrSz2Callable[[ToolCallRequest], ToolMessage | Command]r\ToolMessage | Command)rRrrSz=Callable[[ToolCallRequest], Awaitable[ToolMessage | Command]]r\r^) r: __module__ __qualname____doc__rMr#r2r@rFrUrX __classcell__)r.s@r/rrs _H-1&L * #"]]+ ]  ]  ]]]]] ]~ . &  ,6 =F WZ  @5  5 D5   5 n6  6 O6   6 r3r)ra __future__rrWrNr$typingrlangchain_core.messagesr"langchain.agents.middleware._retryrrrr r !langchain.agents.middleware.typesr collections.abcr r langgraph.typesrrlangchain.toolsrrr3r/rlsF'"  />3'A(n /n r3