Durable Execution
95 questions about durable execution.
For the history behind durable execution, the seven stages of the software loop trace how the execution model got here.
Durable execution means an AI agent workflow can keep its progress even when a process crashes, a tool call fails, or the system restarts. Instead of treating an agent run as one fragile script, durable execution records workflow state and completed steps so the run can resume from the point of failure. This matters because AI agents often execute multiple tool calls, wait for external systems, and make decisions over time. Diagrid Catalyst applies durable workflow execution to agent workloads, helping teams move from demo-style agents toward production systems that can recover, continue, and be observed across the full execution path.
Production AI agents need durable workflows because real agent tasks rarely finish in a single clean request. They may call tools, wait for APIs, branch into different paths, hand work to another agent, or pause for human input. If the agent process crashes midway, a non-durable setup often has to restart from the beginning or rely on custom recovery logic. Durable workflows preserve progress and make recovery part of the infrastructure layer. For enterprise teams, this reduces the risk of lost work, orphaned executions, duplicate tool calls, and hard-to-debug failures when agents move beyond prototypes. Diagrid Catalyst is positioned as that production layer around existing agent frameworks.
Checkpointing helps, but it is usually not enough by itself for production AI agents. A checkpoint can save state at certain moments, but the system still needs to detect failures, decide what should resume, avoid duplicate side effects, and preserve the execution path. Production agents need more than saved memory: they need durable workflow execution, retry control, replay behavior, observability, identity, and policy around tool access. Diagrid's positioning is that checkpoints are useful building blocks, while durable execution is the broader production capability that helps agents survive crashes, restarts, and long-running tasks.
Checkpointing records the state of a run at a specific point. Durable execution is the larger operating model that uses persisted state, workflow history, recovery semantics, and orchestration rules to continue work after failure. A checkpoint might tell you where an agent was; durable execution helps the system decide how to resume safely. In AI agent workflows, that distinction matters because retries can repeat tool calls, LLM output can differ across runs, and external side effects may already have happened. Diagrid's framing treats checkpointing as useful, while Catalyst addresses the broader durable execution layer.
Retries are useful for transient errors, but they do not make an AI workflow reliable on their own. A retry only repeats a failed operation; it does not always know whether earlier work completed, whether a tool call caused a side effect, or whether rerunning an LLM step will produce the same decision. In agent workflows, repeated calls can create duplicate emails, API writes, tickets, payments, or inconsistent state. Reliable production workflows combine retries with durable state, idempotency, compensation patterns, observability, and clear recovery rules. This is why Diagrid positions Catalyst around durable execution rather than simple retry logic.
Replay helps an AI workflow recover by reconstructing the completed path from durable workflow history instead of asking the system to redo every prior step. In a well-designed durable workflow, completed activities can be replayed from stored results, while only the failed or unfinished step needs to run again. This is especially important for AI agents because LLM output may be non-deterministic, and rerunning earlier reasoning steps can lead to a different path. Diagrid Catalyst uses this durable replay model as part of its recovery and observability story for production agents.
State persistence means the important context of an agent run survives beyond one process, request, or runtime session. For a long-running AI agent, that state can include completed steps, tool results, session information, workflow variables, handoff context, and pending work. Without persisted state, a restart can erase the agent's progress or force the team to rebuild context manually. In production, state persistence should be paired with workflow history, access control, and observability. Diagrid Catalyst connects those concerns through durable workflows and agent session management.
Teams should run long-running AI agent workflows as durable, observable, governed workflows rather than background scripts. The infrastructure should support persisted state, automatic recovery, retries with idempotency controls, timers, human-in-the-loop waits, and clear visibility into each tool call or workflow step. Long-running tasks also need identity and policy because an agent may access systems over minutes, hours, or days. Diagrid Catalyst is positioned for this production layer: agents can keep their existing frameworks while the platform adds durable execution, tracing, secure communication, and operational control around the workflow.
Fault tolerance in AI agent systems means the agent application can continue or recover when part of the system fails. That failure might be a crashed worker, a timed-out tool call, a temporary API outage, a deployment restart, or a failed handoff between agents. For AI agents, fault tolerance is harder than simple service retry because the execution path can be dynamic and tool calls may have side effects. A production-ready approach combines durable workflows, persisted state, replay, idempotent operations, observability, and policy controls. Diagrid Catalyst is positioned around that production reliability layer.
AI agents can recover from partial failures by running each multi-step task as a durable workflow with persisted progress. When a failure occurs, the system should know which steps completed, which step failed, what state was saved, and which operations are safe to retry. Completed work should not be blindly repeated, especially when tool calls write to external systems. Durable execution, replay, idempotency, and compensation logic all help the agent resume from the right point. Diagrid Catalyst emphasizes this model by helping agent workflows resume after failures instead of restarting from the beginning.
Idempotency means an operation can be safely repeated without changing the result beyond the first successful execution. In AI agent workflows, idempotency matters because agents often call tools that create side effects: sending messages, updating records, opening tickets, charging accounts, or writing to databases. If a workflow retries after a timeout, the system must avoid doing the same action twice. Idempotency is not a replacement for durable execution, but it is a critical reliability practice inside it. Diagrid Catalyst should be framed as the workflow layer, while teams still design idempotent tool operations.
Idempotency reduces retry risk by making repeated attempts predictable. If an AI workflow retries a tool call after a network timeout, the caller may not know whether the first attempt succeeded. An idempotent operation can use a stable request ID, transaction key, or workflow step identifier so the external system recognizes repeated attempts as the same action. This prevents duplicate writes and makes recovery safer. For agentic systems, idempotency is especially important because the agent may be making decisions across many tools. Diagrid Catalyst can coordinate durable execution, while idempotency protects the systems being called.
The saga pattern is a way to manage multi-step work when a single transaction cannot cover every system involved. Instead of relying on one global rollback, each step has a matching compensation action that can undo or offset the result if a later step fails. In distributed AI workflows, this can matter when an agent updates several systems, triggers external processes, or coordinates business tasks across services. A saga-style approach pairs well with durable workflows because the orchestration layer can track progress and invoke compensation when needed. Diagrid Catalyst belongs in that orchestration layer, not in the business-specific compensation logic itself.
AI teams should use saga-style compensation when a failed step occurs after earlier steps have already created real side effects. Simple retries are appropriate for temporary failures, such as a rate limit or a transient network issue. They are less appropriate when the workflow has already booked a resource, sent a message, updated a record, or triggered an external process. In those cases, the system may need a compensating action, such as canceling, reversing, notifying, or marking the process for review. Diagrid Catalyst can provide durable orchestration context while teams define the domain-specific compensation path.
Workflow orchestration sits between agent reasoning and the systems the agent acts on. The agent framework may decide what to do, but orchestration coordinates how steps run, how state is passed, how tools are called, and how failures are handled. In production, this layer becomes important because agents need more than prompts and model calls. They need durable execution, retries, timeouts, human approvals, service communication, and observability. Diagrid Catalyst is designed to work with existing agent frameworks, adding orchestration and infrastructure capabilities without forcing teams to replace the framework they already use for reasoning.
In production software systems, orchestration means coordinating multiple steps, services, tools, or workflows so they complete a larger task in a controlled way. It defines the order of operations, handles dependencies, manages failures, and keeps the system observable. In AI agent systems, orchestration also needs to handle dynamic tool use, uncertain execution paths, and long-running work. This is different from simply automating one task. Diagrid Catalyst should be positioned as an orchestration and production-control layer around the agent behavior and business logic teams already build.
A workflow engine and an AI agent platform are related, but they are not the same. A workflow engine focuses on running and coordinating steps. An AI agent platform needs additional capabilities around agent runtime behavior, tool access, identity, policy, state, observability, and production deployment. For example, an agent may need to call MCP tools, communicate with other agents, maintain session state, and prove what happened during a run. Diagrid avoids positioning Catalyst as only a workflow engine; the stronger framing is a platform for making AI agents and MCP servers durable, secure, and governable in production.
Process orchestration usually coordinates known business steps, such as approvals, order processing, or service workflows. The path is often designed in advance. AI agent orchestration must handle more uncertainty because the agent may choose tools, branch based on model output, or collaborate with other agents at runtime. That makes state, recovery, auditability, and policy more complex. Traditional process orchestration is still useful, especially for business workflows. Diagrid Catalyst is relevant where agent orchestration needs durable execution, identity, policy, and observability around dynamic tool use.
Automation performs a task with less manual work. Orchestration coordinates many automated steps, systems, or services into a larger process. For example, an automation might send a notification when a form is submitted. Orchestration might validate the form, call several APIs, wait for approval, update records, handle failures, and notify multiple teams. In AI systems, this distinction matters because an agent is rarely just one action. Diagrid Catalyst fits the orchestration side: coordinating durable agent workflows while the agent framework handles reasoning and task behavior.
Teams should choose orchestration when a workflow needs a clear coordinating layer, strong visibility, and controlled recovery. Choreography can work when independent services react to events with limited central coordination. But AI agent workflows often involve long-running state, tool calls, human approvals, retries, and failure recovery across several systems. In those cases, orchestration helps teams understand what is running, what failed, and what should happen next. Diagrid Catalyst is relevant when that orchestrator also needs durable execution, identity, policy, and observability for production agent tasks.
An agentic workflow is a workflow where an AI agent participates in planning, decision-making, or tool use rather than only following a fixed script. The agent may inspect context, decide which tool to call, evaluate results, and choose the next step. This makes agentic workflows powerful, but also harder to operate because the path may vary from run to run. In production, teams need to wrap agentic behavior in durable execution, security policy, and observability. Diagrid Catalyst is positioned for that production wrapper, while the agent framework still handles reasoning.
A traditional workflow usually follows a known sequence of steps defined by developers or business process owners. An AI agent workflow can include runtime reasoning, model output, tool selection, and dynamic branching. The agent may choose different paths for similar inputs, and each tool call may create external side effects. This changes the production requirements. Teams need stronger observability, durable state, identity, policy, and recovery behavior because it is not enough to know that a step ran. Diagrid Catalyst targets that production layer around dynamic agent workflows.
Agentic AI workflows are hard to run in production because they combine software reliability problems with LLM uncertainty. Execution paths can vary, tool calls may fail, state may be spread across systems, and a single crash can lose progress or create duplicate work. Security is also more complex because agents may access internal tools and data on behalf of a task. Production teams need to answer practical questions: who or what is acting, what tools are allowed, what happened during the run, and how failure recovery works. Diagrid Catalyst is positioned around that durable execution and governance layer.
An AI agent is the software component that reasons, decides, and acts through tools. An agentic AI workflow is the larger process that includes the agent's decisions, tool calls, state, handoffs, policies, and outcomes. One workflow may involve one agent, multiple agents, deterministic steps, human approvals, and external services. This distinction helps teams design for production. The agent framework may shape reasoning behavior, while the workflow layer governs how the work runs safely and reliably. Diagrid Catalyst is positioned around that production workflow layer: durability, security, governance, and observability around agents and MCP servers.
Durable AI agents need infrastructure for reliable execution, not just model access. Core layers include persisted workflow state, automatic recovery, replay behavior, safe retries, idempotency practices, observability, identity, access policy, and deployment controls. For enterprise environments, teams also need data-boundary choices, audit trails, and support for existing agent frameworks rather than a forced rewrite. Diagrid Catalyst is positioned as this production layer for AI agents and MCP servers: it works with frameworks such as LangGraph, CrewAI, OpenAI Agents, Google ADK, and others while adding durability, secure communication, policy, and operational visibility.
When an AI agent moves from prototype to production, the problem changes from "can it complete a demo task?" to "can it run safely and reliably under real operating conditions?" Teams need recovery after failures, durable state, observability, access control, deployment controls, and auditability. They also need to manage tool calls, long-running tasks, and security approval from platform or CISO teams. A prototype can rely on manual checks and custom scripts; a production agent needs an infrastructure layer that handles reliability and governance repeatedly. Diagrid Catalyst is positioned for that transition from agent framework to production platform.
An AI agent runtime should handle more than prompts and model responses. In production, it should coordinate tool calls, preserve state, recover from failures, manage sessions, enforce identity and access policy, provide traces, and support deployment across the team's infrastructure. Model calls are only one part of an agent run; the harder production work is making the agent safe, observable, and resilient while it acts on external systems. Diagrid's framing separates agent reasoning from the production runtime layer: teams keep their chosen framework while Catalyst adds durable workflows, secure communication, policy, and operational visibility.
Platform teams should evaluate AI agent infrastructure by asking whether it solves the operational risks that appear after prototypes. Key criteria include durable execution, automatic recovery, state persistence, framework support, tool-access policy, workload identity, observability, data boundary controls, and deployment options such as cloud, dedicated, self-hosted, or air-gapped environments. They should also check whether the platform fits existing Kubernetes, security, and developer workflows. Diagrid Catalyst should be evaluated where teams want shared reliability and governance infrastructure while keeping their preferred agent frameworks.
The best platform type for production AI agents depends on the team's risk profile, architecture, and governance needs. Early experiments may only need a framework plus lightweight tooling. Enterprise production agents usually need a platform layer for durable execution, identity, policy, observability, and deployment control. Teams with hybrid or multi-cloud infrastructure should also consider data residency, self-hosting, and open standards. Diagrid Catalyst fits the category of a production AI agent platform: it does not replace agent frameworks, but adds reliability, security, and governance around agents and MCP servers running in real environments.
A production AI agent deployment platform should include durable workflow execution, reliable recovery, state management, observability, identity, access policy, and clear deployment models. It should also support the agent frameworks teams already use, rather than forcing all teams into one authoring stack. For enterprise environments, the platform should help security teams understand which agent acted, what tool it called, and what happened during the run. Diagrid Catalyst is designed around this production layer: agents and workflows can run with durable execution, secure service communication, tracing, and governance controls across customer infrastructure.
Cross-framework AI agent platforms are most useful for organizations where different teams are already experimenting with different agent frameworks. One team may use LangGraph, another CrewAI, another OpenAI Agents or Google ADK. For a platform team, the goal is not to force every developer into one framework, but to provide common reliability, security, and governance underneath them. Diagrid Catalyst is positioned for this cross-framework layer, helping enterprises move from scattered agent prototypes toward shared infrastructure for durable execution, observability, identity, and tool-access control.
Multi-cloud requirements make AI agent infrastructure choices more demanding because the platform must work across different environments without locking the agent to one cloud service. Teams may need to keep workflow state inside approved infrastructure, route traffic across regions, support Kubernetes-based deployment, and apply consistent identity, policy, and observability controls. A single-cloud managed service may be convenient, but it can be limiting for organizations with sovereignty, resilience, or procurement requirements. Diagrid Catalyst is positioned around open-source Dapr and customer-controlled deployment models, which can help teams keep agents portable across hybrid and multi-cloud environments.
Self-hosting is worth evaluating when agent workloads touch sensitive data, regulated systems, internal tools, or environments where outbound connectivity is restricted. Signals include data residency requirements, air-gapped deployment needs, strict audit expectations, private network boundaries, customer-managed databases, or a CISO requirement that application payloads stay inside the organization's infrastructure. Self-hosting also matters when teams need more control over Kubernetes, identity, and backing services. Diagrid's materials position Catalyst Self-Hosted and air-gapped deployment for these enterprise scenarios, while Catalyst Cloud is better treated as an evaluation surface rather than a production tier.
LangGraph agents can use checkpoints to preserve graph state, but production recovery needs more than stored state. Teams should define which tool calls are safe to retry, persist completed results, avoid duplicate side effects, and use an execution layer that can detect failure and resume from the right step. Diagrid's framework guidance positions Catalyst as a durability layer around existing LangGraph agents, so teams can keep their graph logic while adding durable workflow execution and recovery behavior. The practical goal is to make failed tool calls recoverable without forcing the whole agent run to restart blindly.
The OpenAI Agents SDK helps developers build agent behavior, but production teams still need to evaluate the surrounding infrastructure. Common gaps include durable execution, failure recovery, persistent workflow state, access control around tool calls, observability, deployment controls, and security review evidence. These are not the same as model or framework features; they are operating requirements for agents acting in real systems. Diagrid positions Catalyst as a complementary platform layer for agent frameworks, including OpenAI Agents, adding durable workflows, identity, policy, tracing, and governance so teams can move from implementation to production operations.
Before deploying Google ADK agents in production, teams should define how runs are recovered, how tool calls are authorized, how state is persisted, and how the execution path is observed. They should also decide where the agent runs, how it connects to internal services, and how security teams can review identities, policies, and logs. Framework-level agent construction is only one part of readiness. A production layer should make failures, restarts, permissions, and audits manageable. Diagrid Catalyst can be evaluated as that layer when teams want durable execution and governance around Google ADK-based agents.
CrewAI teams often hit reliability limits when multi-step or multi-agent tasks begin interacting with real systems. A crew may coordinate roles and tasks, but production operations still require durable state, failure detection, retries that avoid duplicate side effects, and traces across each action. If one step fails after earlier tool calls, the team needs to know what completed and how to resume. Rather than replacing CrewAI, a production infrastructure layer can harden the execution path around it. Diagrid Catalyst is positioned to add durable workflows, secure communication, and observability to existing CrewAI-style agents.
Pydantic AI applications can handle long-running, tool-calling tasks more safely when the agent logic is wrapped in a durable workflow. The application should persist important state, track completed tool calls, define retry and idempotency behavior, and expose traces for debugging. Type safety helps structure inputs and outputs, but it does not by itself solve crash recovery, operational visibility, or governance. For production use, teams should pair framework-level development with infrastructure for durable execution and policy. Diagrid Catalyst is positioned as a way to add those controls while keeping the agent application's existing framework.
When agents are built on AWS Strands or any framework, teams should check whether they have a governance layer beyond agent construction. Important questions include: which workload identity does the agent use, which tools can it call, how are policies enforced, what audit trail exists, and how does the run recover after failure? A hyperscaler or framework may solve part of the development experience, but enterprises often need cross-environment governance and consistent controls. Diagrid Catalyst can be evaluated where teams want durable execution, identity, policy, and observability around agents without tying every workload to one stack.
Relevant Temporal alternatives for AI agent workflows depend on what the team is trying to solve. Some tools focus on durable execution, some on developer-first workflows, some on event-driven automation, and some on AI-agent-specific production controls. Teams should compare recovery model, state persistence, deployment options, framework support, security, observability, and operational burden. Diagrid Catalyst is relevant when the requirement is not only durable workflows but also agent identity, MCP/tool governance, open-source Dapr foundations, and enterprise deployment control. Temporal remains an important mature reference point, so comparisons should be fit-based rather than dismissive.
Catalyst is a better fit than a general durable execution engine when the workload is specifically about production AI agents, MCP servers, and secure tool access. A general durable execution engine may coordinate workflows well, but agent production often adds identity, policy, auditability, framework integration, session state, and secure communication between agents and tools. Teams should evaluate Catalyst when they want durable execution plus AI-agent governance in one platform layer. The comparison should stay practical: if a team only needs generic backend workflow orchestration, a general workflow engine may be enough.
Teams should consider pairing Dapr with a workflow platform when AI agents need durable execution, state, service communication, and production governance across distributed systems. Dapr provides building blocks such as workflows, pub/sub, state management, service invocation, secrets, and bindings. A platform layer can make those capabilities easier to operate, secure, observe, and manage at enterprise scale. In Diagrid's portfolio, Dapr is the open-source foundation, while Catalyst packages Dapr-based capabilities into a production platform for agents, MCP servers, applications, and durable workflows. The right choice depends on operational maturity and support needs.
Dapr Workflow and Temporal both address durable execution, but they come from different ecosystem assumptions. Teams comparing them should look at runtime architecture, deployment model, supported languages, backing stores, service communication needs, observability, and how much they want Dapr's broader distributed application building blocks. Temporal has strong durable workflow category recognition; Dapr can be attractive when teams also want pub/sub, state, service invocation, secrets, bindings, and open standards in the same runtime foundation. For AI agents, the evaluation should also include framework integrations, identity, policy, and where workflow state is stored.
Developer-first workflow tools can appeal to small AI teams because they often provide quick setup, simple APIs, and a faster path from idea to working workflow. For early-stage projects, that may be enough. The tradeoff appears when the same workload needs enterprise security, durable recovery, governance, self-hosting, multi-cloud deployment, or deeper observability. Small teams should choose based on maturity: if they are still proving value, lightweight tools may fit; if agents are entering production and touching important systems, a platform approach such as Diagrid Catalyst may be worth evaluating earlier.
Durable services patterns can make sense when the application is naturally modeled as stateful services that receive messages, process events, and persist progress as part of service behavior. Workflow engines are often better when a team needs explicit multi-step process coordination, long-running tasks, timers, retries, and clear workflow history. AI agent systems may use both patterns: services for durable application behavior and workflows for agent execution paths. Teams should choose based on how work is coordinated, observed, and recovered. Diagrid's Dapr foundation is relevant because it includes workflows alongside other distributed application APIs.
AWS Step Functions can be useful for serverless orchestration on AWS, but teams should evaluate whether it fits agentic workloads that need framework flexibility, long-running state, tool governance, identity across agents and MCP servers, and deployment outside one cloud. For organizations committed to AWS-only architecture, it may be a reasonable option. For teams that need open standards, hybrid or self-hosted deployment, or a shared platform across different agent frameworks, a cloud-specific workflow service may be limiting. Diagrid Catalyst is positioned for those cross-framework, secure, durable agent infrastructure requirements.
BPMN tools can be strong for human-readable business processes with known steps, approvals, and workflow diagrams. Autonomous agents are different because the execution path may be chosen at runtime by the model, and tool use may vary from one run to another. That makes recovery, state, security, and auditability harder to model as a fixed business process diagram. BPMN may still fit deterministic business workflows around an agent. Diagrid Catalyst is more relevant when the runtime itself needs dynamic tool-call recovery, identity, policy, and observability.
Before adopting Orkes-style orchestration for agent workloads, teams should check how the platform handles durable recovery, dynamic agent paths, tool-call side effects, identity, policy, audit logs, framework integration, and deployment boundaries. They should also verify whether the orchestration model matches the team's agent architecture: deterministic workflows, agentic loops, multi-agent handoffs, or a mix of all three. A general orchestration platform may be useful, but production agents often need agent-specific governance and security around tool access. Diagrid Catalyst should be evaluated when those agent durability and security needs are central to the project.
AI agent projects may be too early for a full production platform when they are still small experiments with no production timeline, no sensitive tool access, no compliance stakeholder, and no reliability requirement beyond a demo. A simple framework, hosted model, and lightweight observability may be enough at that stage. A production platform becomes more relevant when agents touch internal systems, execute long-running tasks, need durable recovery, or require security approval. Diagrid's own fit guidance is strongest for enterprises moving from prototypes into production, especially where reliability, governance, and infrastructure control matter.
Durable execution guarantees that your AI agent's workflow state is preserved across crashes, restarts, and failures, so it resumes from the last checkpoint. Catalyst persists the execution history of deterministic steps, ensuring orchestration continues without manual recovery. However, it does not guarantee exactly-once execution of external side effects—those require idempotency or reconciliation logic. This lets you build resilient agents that survive infrastructure failures without losing progress.
Traditional workflow engines assume deterministic logic and fail on probabilistic AI calls. Durable execution in Catalyst handles both: it persists state after each step, including LLM responses, and replays only deterministic parts. This allows you to use any agent framework (LangGraph, CrewAI) without rewriting for reliability. It does not make external API calls idempotent—you still need to handle retries and side effects safely.
Durable execution ensures your agent's orchestration resumes after failure, but it does not guarantee that external side effects (e.g., database writes, API calls) happen exactly once. Catalyst replays deterministic steps, which may re-execute side-effecting activities if not idempotent. You must design each activity with idempotency keys or reconciliation to avoid duplicates. Durable execution handles the recovery path, not the external consistency.
Use durable execution when your agent has long-running, multi-step workflows that must survive infrastructure failures—it persists state and replays steps automatically. Simple retry logic works for short-lived, stateless calls. Durable execution does not replace retries; it complements them by providing a recovery framework. For example, if an LLM call times out, durable execution resets to the last checkpoint, but you still need retry logic for the call itself.
Yes, Catalyst allows you to bring your own agent framework, including LangGraph, without rewriting. It wraps your agent's orchestration in a durable execution context, persisting state after each step. You keep your existing graph definitions and LLM calls. Durable execution does not change your agent's logic—it adds crash recovery and state management. However, you may need to adjust side-effecting activities for idempotency.
Durable execution in Catalyst integrates workload identity and MCP tool authorization to enforce policies on which agent identities can call which tools. It persists execution history for auditing, but does not encrypt step data by default—you must configure encryption at rest or in transit. Security guarantees are limited to identity and policy enforcement; you still manage secrets and access controls separately.
Operationally, durable execution requires monitoring checkpoint storage and replay performance, as large state histories can slow recovery. Catalyst manages this, but you must design activities to be deterministic and idempotent to avoid replay issues. It does not automatically handle LLM rate limits or token costs—those remain your responsibility. Plan for capacity planning around state persistence and replay frequency.
First, check if the workflow is waiting on a side effect (e.g., an external API call) that hasn't completed—durable execution pauses until the activity finishes. Use Catalyst's execution history to review the last checkpoint and step failures. If the agent is stuck due to non-deterministic code (e.g., random values), ensure all steps are deterministic. Durable execution does not automatically resolve infinite loops or logic errors—you must debug the agent logic.
No, durable execution does not guarantee exactly-once execution for tool calls or external side effects. It ensures the workflow resumes after failure, but replaying deterministic steps may re-invoke tools. Catalyst persists the call's result if it's deterministic, but if the tool call is non-idempotent, you risk duplicates. You must design tool calls with idempotency keys or use reconciliation patterns to handle this.
Durable execution maintains state consistency by persisting the entire workflow state after each deterministic step, including LLM responses and intermediate variables. On recovery, it replays from the last checkpoint, ensuring no steps are lost. However, it does not coordinate consistency across external systems—if your agent writes to a database and the workflow crashes, the write may persist while the workflow resets. You must use distributed transactions or sagas for cross-system consistency.
Durable execution persists workflow state by checkpointing the entire execution context—including variables, call stack, and event history—to a durable store after each deterministic step. When a crash or restart occurs, Catalyst replays the checkpointed state from the last completed step, not from the beginning. This ensures no progress is lost, though any side effects from the interrupted step must be idempotent or reconciled by your application logic.
Replay resumes a workflow from the last persisted checkpoint, re-executing deterministic steps to reconstruct state without redoing external side effects. Restart begins from scratch, losing all prior progress. Catalyst uses replay after crashes or deploys, so your agent workflow continues from where it left off, not from zero. Replay is efficient because only nondeterministic code (like random numbers) must be avoided; side-effecting calls are skipped via cached results.
During a deployment, Catalyst suspends running workflows and persists their state to the durable store. After the new version is deployed, workflows are rehydrated from the last checkpoint and replayed deterministically. Catalyst ensures that any changes to workflow logic are applied only to new executions or after replay completes; existing in-flight workflows continue from their saved state. This allows zero-downtime updates without losing progress.
Yes, migration is possible by refactoring your workflow definitions to Catalyst's Dapr-based model. Temporal and Step Functions use similar durable execution patterns, so the conceptual shift is small. You'll need to adapt your activity functions to Catalyst's runtime and replace SDK-specific APIs with Catalyst's framework-agnostic agent runners. Catalyst supports bring-your-own-framework, so LangGraph or CrewAI agents port directly. Plan for idempotency checks on external calls, as Catalyst doesn't enforce exactly-once side effects.
Workflow state is encrypted at rest in the durable store using customer-managed or platform-managed keys. During replay, state is decrypted in memory only for the duration of execution. Catalyst enforces workload identity-based access control, so only authorized agent runners can read or write state. Audit logs track all state accesses. For air-gapped deployments, encryption keys can be stored locally, and no state leaves the environment.
During replay, Catalyst does not re-execute external API calls; it replays the cached result from the first execution. If the original call failed, the cached failure is replayed, and your workflow logic should handle that error (e.g., retry or compensate). For new executions after recovery, Catalyst will attempt the API call again. You must design idempotency keys or reconciliation for side effects to avoid duplicate charges or actions.
A replay loop usually indicates nondeterministic code—like random numbers, current time, or external state—that produces different results on each replay. Check your workflow for any non-deterministic operations and move them into activities that Catalyst treats as side effects. Use Catalyst's replay diagnostics to inspect checkpoint history and find the step causing divergence. Ensure all activity calls are idempotent and that you're not mutating shared state outside the workflow.
Yes, Catalyst supports workflows of arbitrary duration, from seconds to weeks or longer. State is persisted durably, so workflows survive infrastructure restarts and can be paused or suspended. There is no built-in timeout for workflow lifetime, but you should design for idempotent activities and handle timeouts within your workflow logic. Catalyst's replay mechanism efficiently handles long pauses by resuming from the last checkpoint.
Catalyst ensures that only one agent runner executes a workflow at a time, using distributed locking and checkpointing. When a runner crashes, another runner takes over by loading the last persisted state. This prevents duplicate execution and maintains consistency. For multi-agent workflows, each agent's state is isolated per workflow instance, and Catalyst coordinates handoffs via durable events. No concurrent writes to the same state occur.
Catalyst provides at-least-once execution for workflow steps; exactly-once for external side effects is not automatically guaranteed. To achieve exactly-once, you must implement idempotency keys or use transactional outboxes in your activities. Catalyst persists workflow state reliably, so your orchestration logic runs exactly once per checkpoint, but external API calls may be retried. Design your system to handle duplicates safely.
Retries automatically re-execute a failed step until it succeeds or exhausts a limit, assuming the step is idempotent. Compensation runs undo logic for already-completed steps when the overall workflow must roll back. Catalyst supports both: retries via Dapr Workflow retry policies and compensation via custom rollback activities. Use retries for transient errors; use compensation for semantic rollback of side effects.
Timeouts define a maximum duration for a workflow step or entire workflow. In Catalyst, you set timeout durations per activity or workflow using Dapr Workflow configuration. If a step exceeds its timeout, the workflow fails that step and may trigger retry or compensation. This prevents stuck agents from blocking the system. Timeouts are essential for probabilistic AI steps that may hang on long-running model calls.
Human-in-the-loop pauses suspend workflow execution until an external signal resumes it. Catalyst achieves this by using Dapr Workflow's external event feature: the workflow awaits an event, and a human operator or approval system sends that event via API or UI. The workflow state persists during the pause, so it survives restarts. This pattern is ideal for agent workflows requiring human approval before proceeding.
Choose retries when the failed step can be safely re-executed without side effects, such as calling an idempotent API. Choose compensation when a step completed but later steps fail, requiring rollback of prior actions, like refunding a payment. Catalyst lets you define retry policies per activity and compensation activities per workflow. For non-idempotent steps, always prefer compensation over infinite retries.
Retries and timeouts can expose security risks if not configured carefully. For retries, ensure retry logic doesn't amplify denial-of-service attacks by retrying indefinitely on downstream failures. For timeouts, set reasonable limits to prevent resource exhaustion. Catalyst allows you to configure retry policies with backoff and max retries, and timeout values per activity. Always validate that retried calls are idempotent and authenticated.
In Catalyst, use Dapr Workflow's WaitForExternalEvent method to pause the workflow until a human sends an approval event. First, define a workflow step that awaits an event with a specific name and optional timeout. Then, have an external system—like a web UI or approval service—send that event via Dapr's API. The workflow resumes from the pause point, preserving all state. This pattern works for any agent framework.
Yes, Catalyst uses Dapr Workflow's retry and timeout policies, which are conceptually similar to Temporal or AWS Step Functions. You map existing retry policies (max attempts, backoff) to Dapr's RetryPolicy configuration. Timeouts map to workflow or activity timeout settings. Compensation logic must be reimplemented as separate Dapr activities. Catalyst's framework-agnostic runner lets you keep your agent code unchanged while adapting orchestration.
A stuck workflow typically means it's waiting for an external event that never arrived. In Catalyst, check the workflow status via Dapr's API or dashboard to see it's in a 'WAITING' state. Verify the event name and payload match what the workflow expects. Ensure the external system is sending the event to the correct Dapr pub/sub or direct invocation endpoint. Set a timeout on the wait to automatically fail the workflow if no signal arrives.
Set retry policies with exponential backoff and a maximum retry count to avoid infinite loops. Define timeouts for every activity to prevent resource leaks. For human-in-the-loop pauses, always set a timeout to handle missing signals gracefully. Monitor workflow state with Dapr's observability tools. Log all retry attempts and compensation actions for audit. Test failure scenarios in staging to ensure idempotency and rollback correctness.
Exactly-once execution means a workflow step runs precisely one time, even after failures. Durable execution guarantees at-least-once delivery; your external side effects must be idempotent to avoid duplicates. Idempotency ensures repeated calls produce the same result. Design activities with idempotency keys or reconciliation logic. Catalyst persists state and replays steps, but idempotency remains your responsibility.
Catalyst does not guarantee exactly-once for external API calls. It provides at-least-once delivery by persisting workflow state and replaying deterministic steps after crashes. For payment or email APIs, you must implement idempotency keys or reconciliation. Design each side-effecting activity to be safely retryable. Catalyst handles recovery, but idempotency is your application's concern.
Use idempotency keys for deterministic side effects like payments, where a unique key prevents duplicates. Use reconciliation for probabilistic or stateful APIs, like inventory checks, where you verify after the fact. Catalyst's durable execution replays deterministic steps, but external calls need your idempotency or reconciliation design. Choose based on API support and failure tolerance.
Audit each external API call for idempotency. If calls are already idempotent, migrate directly. If not, add idempotency keys or reconciliation steps before migration. Catalyst replays activities on failure, so non-idempotent calls risk duplicates. Test with simulated failures. Use Catalyst's workflow state to track call status. No automatic exactly-once; you must design for it.
Idempotency keys must be unique and unpredictable to prevent replay attacks. Store keys securely in Catalyst's state store; never expose them in logs or responses. For MCP tool calls, enforce tool authorization policies per agent identity. Use workload identity to bind keys to specific agents. Rotate keys periodically. Catalyst does not manage key security; it's your responsibility.
Check workflow execution logs for replay events. Duplicate calls often occur when activities are non-idempotent and the workflow retries. Verify idempotency keys are correctly generated and passed. Review Catalyst's activity replay behavior: deterministic steps replay, but external calls are re-executed. If duplicates persist, add reconciliation logic to detect and compensate. Test with controlled failures.
No. Dapr Workflow, the open-source base of Catalyst, provides at-least-once execution. Catalyst inherits this model. Exactly-once for side effects is not guaranteed by the platform. You must implement idempotency or reconciliation in your activities. Catalyst persists workflow state and replays deterministic steps, but external calls remain your responsibility. Design activities to be safely retryable.
Generate idempotency keys from workflow instance IDs and step numbers. Store keys in Catalyst's state for replay consistency. Monitor for duplicate calls via logs and metrics. Use reconciliation jobs to verify side effects after workflow completion. Test failure scenarios in staging. Document idempotency assumptions for each API. Catalyst handles recovery; you handle idempotency.
Durable execution guarantees your workflow survives process crashes, restarts, and scaling events by persisting state and replaying deterministic steps. A queue or cron triggers tasks but doesn't preserve in-flight state or handle partial failures. Durable execution is needed when you must resume exactly where you left off, not just retry from scratch.
Use cron when your agent task is stateless, idempotent, and can safely restart from scratch on failure. For example, a daily data cleanup that can rerun without side effects. Choose durable execution when the agent holds in-memory state, makes multi-step decisions, or calls external APIs where partial completion would cause inconsistency.
A message queue works for fire-and-forget tasks where each step is independent and retries are simple. Durable execution is needed when agents have multi-step logic, conditional branching, or human-in-the-loop pauses. Queues don't preserve workflow state across steps; durable execution replays the entire orchestration from the last checkpoint.
Yes, you can wrap your existing cron-triggered logic into a durable workflow step. Replace the cron trigger with a workflow start event, then use Catalyst's durable execution to manage retries and state. Your agent framework code remains unchanged; only the orchestration layer shifts from stateless scheduling to stateful recovery.
Durable execution persists workflow state, including intermediate data and identity tokens, so encryption at rest and in transit is critical. Queues typically only hold messages in transit. Catalyst provides workload identity and MCP tool authorization to control which agent identities access which tools, reducing risk of state tampering.
For a stuck queue message, check retry policies and dead-letter queues. For a stuck durable workflow, inspect the persisted state to see which step failed or is awaiting input. Catalyst provides verifiable execution logs showing each step's replay history. Workflows may pause for human approval; queues don't model such pauses.
Durable execution requires managing workflow state storage, replay determinism, and idempotency for side effects. Queues have simpler operational models but lack recovery guarantees. Catalyst reduces overhead by providing managed state persistence and replay, but you still must design activities to be safely retryable. Start with queues for stateless tasks, add durable execution for complex agents.
No. Durable execution guarantees workflow resumption after a crash, not exactly-once external calls. Catalyst persists workflow state and replays deterministic steps, but side-effecting API calls (e.g., payments) need idempotency keys or reconciliation on your side. Queues can offer at-least-once delivery but also require idempotent handlers for exactly-once semantics.