Imported from zhoudongchao9-cloud/blueprint-repl (crates/core/AGENTS.md). Install upstream with npx skills add zhoudongchao9-cloud/blueprint-repl --skill core. Copyright stays with the author.

core

Purpose

Crate blueprint-core: Foundation crate defining the job system primitives that the entire Blueprint SDK builds upon. Provides the Job trait, JobCall request type (modeled after HTTP's Request), JobResult response type, extraction traits (FromJobCall, FromJobCallParts), extension traits for job call manipulation, and feature-gated tracing macros. Designed as a no_std crate with alloc support.

Contents (one hop)

Subdirectories

• docs/ - Developer documentation: jobs_intro.md (job system introduction), debugging_job_type_errors.md (troubleshooting guide for job type errors).
• src/ - Core modules: job/ (Job trait, JobCall, JobResult, JobId), extract/ (FromJobCall, FromJobCallParts extraction traits), ext_traits/ (extension traits for job call parts), error.rs, extensions.rs (type-map extensions), metadata.rs, macros.rs (internal helper macros).

Files

• CHANGELOG.md - Version history.
• Cargo.toml - Crate manifest (blueprint-core). Deps: bytes, futures-util, pin-project-lite, tower, hashbrown, tiny-keccak, tracing. Features: std, tracing.
• README.md - Crate documentation.

Key APIs (no snippets)

• Job trait -- defines a blueprint job handler that processes JobCall requests.
• JobCall -- the request type for job invocations, containing headers, extensions, and a body (similar to HTTP Request).
• JobResult -- the response type for job completions.
• JobId -- unique identifier for a job type.
• FromJobCall / FromJobCallParts -- extraction traits for pulling typed data from job calls (similar to Axum extractors).
• IntoJobResult / IntoJobResultParts -- conversion traits for producing job results.
• JobCallExt / JobCallPartsExt -- extension traits for manipulating job call components.
• Error -- core error type.
• Tracing macros (info!, warn!, error!, debug!, trace!) -- feature-gated wrappers around tracing that compile to no-ops when the tracing feature is disabled.

Relationships

• Foundation dependency for nearly every other crate in the workspace.
• Depended on by blueprint-runner, blueprint-router, blueprint-clients, blueprint-auth, blueprint-faas, blueprint-remote-providers, and more.
• Uses tower for service composition patterns.
• no_std compatible with alloc, making it usable in constrained environments.