iceberg-rust

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# Apache Iceberg Rust — Agent Instructions

This file provides repository-specific guidance for automated agents working
in this repository.

## Comments, docs, and diff scope

Default to no comment. Leave existing comments as they are unless you change
the code they describe or they are wrong.

- Comment only what the code cannot say: invariants, non-obvious
  constraints, links to external behavior. Do not restate the code.
- Do not describe how the code changed or explain review history
  ("previously", "instead of", "unlike X"). Put that in the commit message
  or PR description.
- Public items get a one-line doc summary of what they do for the caller,
  not how. Expand only for contract the caller must know, such as the
  errors it returns (`# Errors`) or when it panics (`# Panics`).
- Test names say what they check. Do not narrate asserts.
- Cover the edge cases and error paths the change adds, not only the
  happy path.
- Build the expected value and assert equality with it, rather than
  checking fields one at a time.
- Do not add tests that duplicate existing coverage.
- Do not rename, reformat, refactor, or reorder code unrelated to the
  change. A bug fix does not carry an API redesign.
- Reuse existing helpers, types, and test fixtures (such as
  `TableTestFixture`) before adding new ones. Use arrow-rs kernels
  instead of reimplementing them.
- Use the narrowest visibility that works. Make items `pub` only when they
  are part of the API the change intends to expose. Run
  `make generate-public-api` to update each crate's `public-api.txt`, and
  check its diff for API growth.

## Pull requests

- Follow the PR template. Keep each section short: the problem, the
  approach, and anything a reviewer would not guess from the diff. In
  AI Disclosure, name the areas of uncertainty or assumptions a reviewer
  should focus on.
- Do not restate the diff: no file-by-file walkthroughs, per-function
  summaries, or "changes made" checklists.

## Security Model

When assessing potential vulnerabilities or calibrating automated security
findings, use [`SECURITY-THREAT-MODEL.md`](SECURITY-THREAT-MODEL.md) as the
authoritative detailed description of this repository's security boundaries,
trust assumptions, and non-boundaries.

More agent context in apache/iceberg-rust

One other file this repository gives its agents.