proposals

name	Proposals
description	Instructions for writing, submitting, and managing Carbon evolution proposals.

Proposals

Overview

This skill provides instructions and best practices for working with proposals. Only create a proposal when explicitly directed as part of the task.

Make sure to confirm the desired title for the proposal as that will govern the filename.

Create a new proposal

1. Use the helper script: Run ./proposals/scripts/new_proposal.py "Title" to create a templated file and instructions for setting up the PR.
2. Proposal file: The file will be named proposals/p######-title.md, where ###### is the 6-digit GitHub pull request number and title is a slugified version of the proposal title.
3. Template: Follow the structure in proposals/scripts/template.md, noting the specific TODO instructions in each section for the content that should be included there.
4. PR description: Update the pull request description to match the abstract section in the proposal document.

[!IMPORTANT] Do not mark the PR ready for review. The user must have the opportunity to review the proposal produced before asking for any review.

Writing style and best practices

• Skimmable: Use BLUF (Bottom Line Up Front) or Inverted Pyramid style. Keep it brief, focused, and technical.
• Match existing proposal style: Review existing proposals (preferring more recent ones with higher numbers) to understand the expected style, wording, and nature of content to include.
• Connect to goals: In the Rationale section, link to specific goals in /docs/project/goals.md and principles in /docs/project/principles (e.g., error_handling.md, one_way.md).
• Living design: If the proposal updates design documentation, include those changes in the PR if possible. If deferred, add "TODO" comments pointing to the proposal (e.g., > **TODO:** Document ... adopted in [p######](/proposals/p######-title.md)). For pervasive changes, file a GitHub issue instead of adding many TODOs.

Alternatives considered and leads decisions

There are always alternatives to a proposal, and the proposal should carefully include sections describing all of them and the rationale for not selecting them. Any living design document updates should focus on fully describing the end-state design, and the key motivating aspects of that design. The main proposal should focus on what is changing and why it is changing, and should leave detailed description of the resulting design to the living design document, and why not rationale to the description of each alternative.

• Cover all the alternatives: Make sure to describe any alternatives considered, even if minor or rejected early.
• Be specific: Don't be vague about any of the alternatives, or the rationale for not choosing them.
• Connect to goals or principles: In addition to the rationale section, one of the best rationale structures for rejecting an alternative connects that choice back to the goals or principles relevant.
• Always frame as a tradeoff: Selecting the proposed direction instead of an alternative is always a tradeoff, with both advantages and disadvantages.
• Where relevant, cite the leads issue that decides against an alternative, in addition to summarizing the key points, tradeoffs, and rationale for the decision.

[!IMPORTANT] Don't just list the alternatives, create a sub-section for each alternative and carefully describe the alternative, the advantages, disadvantages and what the core of the decision is to reject each alternative.

[!IMPORTANT] Carefully research each alternative in the leads issue in order to provide this clear and comprehensive explanation.

Building from a leads issue

Sometimes a proposal is specifically documenting and formalizing a decided leads issue. When this is the case, carefully research that leads issue, reading the original issue text and every comment on the issue. Also read any linked Google documents, linked issues, examples, gists, or other supplemental information cited.

• Summarize the leads issue: Ensure you provide a high level summary of the decided direction of the leads issue as the proposal.
• Capture and document every key aspect of the decision made and factor that led to the decision. It is important that the proposal stands alone, and the leads issue is merely cited for context and history.
• Stay grounded: Only include alternatives, rationale, and arguments based on what you find in the issue and related documents. No new information should be in the proposal.

Use the gh command line tool to query leads issues in order to carefully examine all of the comments. Follow any mentioned links to gather more data. Refer to the GitHub CLI usage skill for detailed instructions on using the gh tool.

Ask the user to clarify any aspects of the leads issue that are unclear rather than continuing to edit the proposal. If there are questions that you don't find an answer to in the issue, ask this to the user and let them provide an answer that you use as the basis of what to include.

Examples are golden

Heavily leverage examples to illustrate both the specifics of the design being proposed, and the nature of the change being proposed. More examples to illustrate more aspects, corner cases, or provide a more complete understanding are almost always good. Comments in example code should focus on what that part of the example illustrates from the proposal.

Keep the PR description in sync with the abstract

Whenever you edit the abstract or notice differences from the PR description, you should update the PR description to match the abstract. The only exception is to retain any "Assisted-by" or other tags at the end of the description that are only needed there and not in the abstract.

If you are creating or updating a proposal, make sure the PR description in question contains an Assisted-by: tag that is appropriate for describing which AI tool is being used.