> ## Documentation Index > Fetch the complete documentation index at: https://docs-code.palyra.com/llms.txt > Use this file to discover all available pages before exploring further. # Core Daemon Architecture (palyra-daemon)
Relevant source files The following files were used as context for generating this wiki page: * crates/palyra-common/src/tool\_catalog.rs * crates/palyra-daemon/src/application/channel\_turn/mod.rs * crates/palyra-daemon/src/application/context\_engine.rs * crates/palyra-daemon/src/application/context\_references.rs * crates/palyra-daemon/src/application/mod.rs * crates/palyra-daemon/src/application/route\_message/orchestration.rs * crates/palyra-daemon/src/application/run\_stream/agent\_loop.rs * crates/palyra-daemon/src/application/run\_stream/orchestration.rs * crates/palyra-daemon/src/application/run\_stream/tool\_flow\.rs * crates/palyra-daemon/src/application/tool\_runtime/mod.rs * crates/palyra-daemon/src/gateway.rs * crates/palyra-daemon/src/gateway/runtime.rs * crates/palyra-daemon/src/journal.rs * crates/palyra-daemon/src/lib.rs * crates/palyra-daemon/src/tool\_posture.rs * crates/palyra-daemon/src/tool\_protocol.rs * crates/palyra-daemon/src/transport/grpc/services/gateway/service.rs * crates/palyra-daemon/src/transport/http/handlers/console/diagnostics.rs * crates/palyra-daemon/src/transport/http/router.rs * crates/palyra-daemon/tests/gateway\_grpc.rs * crates/palyra-daemon/tests/golden/current\_state\_inventory.json
The `palyrad` daemon is the central hub of the Palyra ecosystem. It hosts the gateway runtime, model provider adapters, tool execution backends, and the durable journal in a single process [crates/palyra-daemon/src/lib.rs#1-10](http://crates/palyra-daemon/src/lib.rs#1-10). It manages the entire lifecycle of agent interactions, from inbound message routing to iterative tool execution and post-run learning. ## System Hub: GatewayRuntimeState The core of the daemon is the `GatewayRuntimeState`. This structure acts as the shared coordinator for all transport surfaces (gRPC, HTTP, and QUIC), providing a unified interface to the underlying subsystems [crates/palyra-daemon/src/gateway/runtime.rs#1-12](http://crates/palyra-daemon/src/gateway/runtime.rs#1-12). ### Subsystem Interconnection The daemon organizes its logic into several major domains that interact through the gateway runtime: * **Transport Layer**: Handles protocol-specific communication (Axum for HTTP, Tonic for gRPC) and maps external requests into internal gateway commands [crates/palyra-daemon/src/transport/http/router.rs#1-7](http://crates/palyra-daemon/src/transport/http/router.rs#1-7). * **Orchestration**: Manages the `RunStateMachine`, transitioning agents through phases like `Queued`, `Running`, and `Waiting` [crates/palyra-daemon/src/orchestrator.rs#107-107](http://crates/palyra-daemon/src/orchestrator.rs#107-107). * **Journaling**: Provides a tamper-evident, SQLite-backed audit log and durable storage for sessions, tape, and memory [crates/palyra-daemon/src/journal.rs#1-15](http://crates/palyra-daemon/src/journal.rs#1-15). * **Tool Runtime**: A secure dispatch layer that executes tools (e.g., shell commands, wasm plugins) under strict policy control [crates/palyra-daemon/src/tool\_protocol.rs#1-11](http://crates/palyra-daemon/src/tool_protocol.rs#1-11). ### Daemon Entity Map The following diagram illustrates how high-level architectural concepts map to specific code entities within the `palyra-daemon` crate. ```mermaid theme={null} graph TD subgraph "Transport Layer (Code Entity Space)" HTTP["transport::http::router::build_router"] GRPC["transport::grpc::services::gateway::GatewayServiceImpl"] end subgraph "Core Hub" GRS["gateway::runtime::GatewayRuntimeState"] end subgraph "Orchestration & Logic" RSM["orchestrator::RunStateMachine"] AL["application::run_stream::agent_loop"] TR["application::tool_registry::ToolCatalog"] end subgraph "Persistence" JS["journal::JournalStore (SQLite)"] end HTTP --> GRS GRPC --> GRS GRS --> RSM RSM --> AL AL --> TR GRS --> JS ``` **Sources:** [crates/palyra-daemon/src/lib.rs#14-27](http://crates/palyra-daemon/src/lib.rs#14-27), [crates/palyra-daemon/src/gateway/runtime.rs#1-12](http://crates/palyra-daemon/src/gateway/runtime.rs#1-12), [crates/palyra-daemon/src/application/mod.rs#1-5](http://crates/palyra-daemon/src/application/mod.rs#1-5) ## Major Subsystems The daemon's functionality is partitioned into specialized subsystems. Detailed documentation for each can be found in their respective child pages. ### Gateway Runtime and Session Lifecycle The gateway manages `OrchestratorSessionRecord` and `RunLifecycleState`. It handles inbound message admission via the `InboundCoalescer` and ensures that sessions are resolved and cleaned up properly [crates/palyra-daemon/src/gateway/runtime.rs#7-12](http://crates/palyra-daemon/src/gateway/runtime.rs#7-12). * For details, see [Gateway Runtime and Session Lifecycle](/core_daemon_architecture_palyra-daemon/gateway_runtime_and_session_lifecycle). ### Agent Loop and Run Orchestration The `AgentRunLoopState` drives the iterative process of prompting a model, parsing tool calls, and feeding results back. This loop is recorded on an append-only `Tape` for determinism and auditability [crates/palyra-daemon/src/application/run\_stream/orchestration.rs#1-15](http://crates/palyra-daemon/src/application/run_stream/orchestration.rs#1-15). * For details, see [Agent Loop and Run Orchestration](/core_daemon_architecture_palyra-daemon/agent_loop_and_run_orchestration). ### Journal Store and Audit System The `JournalStore` is a SQLite database operating in WAL mode. It implements a SHA-256 hash-chain to ensure that every `JournalEventRecord` is tamper-evident. It also handles sensitive data redaction before persistence [crates/palyra-daemon/src/journal.rs#1-20](http://crates/palyra-daemon/src/journal.rs#1-20). * For details, see [Journal Store and Audit System](/core_daemon_architecture_palyra-daemon/journal_store_and_audit_system). ### Transport Layer: HTTP, gRPC, and QUIC The daemon exposes multiple interfaces. The Axum-based HTTP router serves the Web Console and Admin APIs, while gRPC services handle high-performance communication for tools and remote workers [crates/palyra-daemon/src/transport/http/router.rs#25-38](http://crates/palyra-daemon/src/transport/http/router.rs#25-38). * For details, see [Transport Layer: HTTP, gRPC, and QUIC](/core_daemon_architecture_palyra-daemon/transport_layer_http_grpc_and_quic). ## Request Flow: Natural Language to Code Execution This diagram traces the path of a user request from the "Natural Language Space" (an inbound message) through the internal "Code Entity Space" until a tool is executed. ```mermaid theme={null} sequenceDiagram participant User as "User (Natural Language)" participant Router as "application::route_message" participant Coalescer as "application::inbound_coalescer" participant Orchestrator as "application::run_stream::process_run_stream_message" participant Loop as "application::run_stream::agent_loop" participant Tool as "tool_protocol::execute_tool_call" User->>Router: "Inbound Message" Router->>Coalescer: "Coalesce Window" Coalescer->>Orchestrator: "Start Run" loop Agent Iteration Orchestrator->>Loop: "Next Step" Loop->>Tool: "execute_tool_call(proposal)" Tool-->>Loop: "ToolExecutionOutcome" end Loop-->>User: "Final Answer" ``` **Sources:** [crates/palyra-daemon/src/application/mod.rs#47-48](http://crates/palyra-daemon/src/application/mod.rs#47-48), [crates/palyra-daemon/src/application/run\_stream/orchestration.rs#3-9](http://crates/palyra-daemon/src/application/run_stream/orchestration.rs#3-9), [crates/palyra-daemon/src/tool\_protocol.rs#6-11](http://crates/palyra-daemon/src/tool_protocol.rs#6-11) ## Security and Governance The daemon enforces a "deny-by-default" security posture. Every tool call is gated by `decide_tool_call`, which evaluates the request against Cedar policies [crates/palyra-daemon/src/tool\_protocol.rs#4-5](http://crates/palyra-daemon/src/tool_protocol.rs#4-5). Security-relevant invariants, such as execution limits and resource cleanup (e.g., stale PID files, browser sessions), are managed centrally within the gateway hub [crates/palyra-daemon/src/gateway.rs#9-11](http://crates/palyra-daemon/src/gateway.rs#9-11). **Sources:** [crates/palyra-daemon/src/gateway.rs#1-11](http://crates/palyra-daemon/src/gateway.rs#1-11), [crates/palyra-daemon/src/tool\_protocol.rs#1-15](http://crates/palyra-daemon/src/tool_protocol.rs#1-15) ## Child Pages * [Gateway Runtime and Session Lifecycle](/core_daemon_architecture_palyra-daemon/gateway_runtime_and_session_lifecycle) * [Agent Loop and Run Orchestration](/core_daemon_architecture_palyra-daemon/agent_loop_and_run_orchestration) * [Journal Store and Audit System](/core_daemon_architecture_palyra-daemon/journal_store_and_audit_system) * [Transport Layer: HTTP, gRPC, and QUIC](/core_daemon_architecture_palyra-daemon/transport_layer_http_grpc_and_quic)