machenjie python-professional-usage
Registry Trigger
Use when
- Python code changes import or initialization, async and blocking work, owned resources, public typing, shared mutability, or serialization behavior.
- Python runtime semantics can change failure, cleanup, cancellation, isolation, or consumer compatibility in the current scope.
Do not use when
- The open decision is language/runtime selection, dependency policy, build mechanics, test strategy, or a measured performance bottleneck.
- No Python-specific runtime or data boundary changes.
Skill Role
Protect Python import and initialization behavior, async and blocking boundaries, resource lifetime, dynamic type and mutability hazards, and serialization semantics.
High-Value Rules
- Identify import side effects, ordering, reload, fork/spawn, and failure behavior.
- Reject irreversible external effects during module import. Permit explicit immutable environment or configuration reads when deterministic, side-effect-bounded, reload/fork-safe, failure-defined, and validated across supported entrypoints.
- Classify blocking calls, spawned tasks, cancellation, exception observation, and context propagation on async paths.
- Bind files, responses, sessions, cursors, temporary resources, and locks to an explicit cleanup owner.
- Parse untrusted values before relying on static types; preserve missing,
None, falsey, subclass, and coercion semantics. - Define reset and synchronization ownership for mutable defaults, caches, and process or task globals.
- Bound serialization by format, version, admitted types, unknown fields, numeric/time semantics, and construction hooks.
- Preserve exception causes, cleanup, partial state, transaction outcome, and retry classification across layers.
Anti-Patterns
- An async function calls blocking code or starts background work whose lifetime and failure have no owner.
- Import performs network, migration, registration, or mutable or implicit configuration work that changes under reload, workers, or fork/spawn.
- A type annotation,
Any, cast, or successful deserialize is treated as proof that runtime input is valid and compatible. - A mutable default, cached singleton, or shallow copy leaks state between requests or tests, while cleanup covers the happy path alone.
Stop Conditions
- Route language, package, build, test, and performance decisions to their specialist owners.
- Route hostile deserialization or command execution to
security-privacy-gate, public schemas todata-api-contract-changer, and money or timezone semantics toi18n-timezone-money-safety.
Output Contract
- Python boundary decision with inspected import and initialization, async and cancellation, resource lifetime, typing and mutability, serialization and exception behavior, validation evidence, proof limits, residual risk, and specialist handoffs
Targeted References
| Path | Type | Load when | Do not load when | Required by | Required output |
|---|---|---|---|---|---|
| benchmarks and patterns | benchmark-pattern | Python change crosses import async resource mutability typing serialization or exception boundary whose failure semantics remain unclear | Current Python entrypoints value contracts and focused checks settle the changed boundary | task-agent, analysis-agent, review-agent | option-comparison, selected-approach |