97

Use when designing a public API, an exported function signature, a module boundary, an exported type/interface, or any contract other code will depend on

Use when about to refactor, restructure, rename across files, or "clean up" existing code

Use when authoring or changing build scripts, CI workflows, deploy pipelines, repo setup files, or evaluating a new tool/dependency for adoption into the project

Use when introducing a new top-level type, table, or domain concept; renaming an existing domain concept; or choosing where state lives (in-memory vs persistent)

Use when adding error handling to a call that can fail, comparing or calculating with floating-point numbers, writing concurrent or parallel code, calling a remote process or another service, adding a singleton or globally-shared mutable state, choosing a data structure for a hot path, or adding/changing log statements

Use when adding a request handler, RPC, or background job that will run in production; adding tracing, metrics, or structured-log calls; or making cross-process diagnosability decisions

Use when about to commit, finish a task, open a PR, summarize work for the human partner, or when the human partner asks for a review or hand-off — NOT just on autonomous commits, which are rare in OpenCode usage

Use when parsing user input, writing/executing SQL or shell commands, handling secrets/tokens/credentials, hashing passwords, adding/changing an auth check, deserializing untrusted data, or constructing file paths/URLs from input

Use when writing new tests, designing test data, naming a test, choosing what to assert, or writing test helpers/mocks/fixtures

Use when starting any coding task — establishes the 97 trigger map so principles fire when relevant

Use when gathering or interpreting requirements, estimating effort, or communicating with stakeholders/customers about what to build

Use when adding a new function/class, naming a new entity, or modifying ≥3 lines of non-trivial logic

1 hook across 1 event