D884 — Cartographer is developed with Claude Code, Kiro, OpenCode and Copilot CLI, on Claude models, with five subagents

Superseded by D992: the repository is developed with Claude Code only; the Kiro, OpenCode and Copilot CLI surfaces and the .agents/skills/ tree are removed.

Decision. The clients this repository is equipped to be developed with are Claude Code, Kiro, OpenCode and Copilot CLI, and any of the four runs the whole workflow (plan-issue, implement-issue, live-dev, review-pr, harness-watch) with the same subagents. Codex and Antigravity leave the development tooling: their agent files, the Codex UI metadata of the skills and the Codex-only gates are deleted. Product support for them (the configurator, the provisioning matrix, the docs/harnesses.md ledger) is a different thing and does not change.

Every subagent runs on a Claude model, written the way each client spells it: Claude Code claude-sonnet-5-5, Kiro and Copilot CLI claude-sonnet-5.5, OpenCode anthropic/claude-sonnet-5-5; the new read-only reader runs on Haiku 5.5 (claude-haiku-5-5, claude-haiku-5.5, anthropic/claude-haiku-5-5). reader reads one voluminous source and returns a digest: the failed log of a red CI run, or one client's release notes for harness-watch. The reviewers stay on Sonnet.

Each agent exists in four files: .claude/agents/<n>.md, .kiro/agents/<n>.json, .opencode/agents/<n>.md (mode: subagent; reader also permission.edit: deny) and .github/agents/<n>.agent.md. TestRepoSubagentsSayTheSameThingOnEveryClient checks that the body, the description and the model translated by that rule agree with the Claude file, and refuses a client file with no Claude counterpart. The skills stay once in .agents/skills/, with a symlink bridge .opencode/skills/ beside .claude/skills/ and .kiro/skills/; Copilot CLI reads .agents/skills/ natively.

This partly supersedes D327 (the model pins: Codex's terra-6 goes, the rest becomes the rule above), D203 (Codex as the reason .agents/skills is the canonical directory: Copilot CLI reads it natively, and nothing else about the layout changes) and D364 (.agents/agents as a development cell: the workspace layer of Antigravity is no longer one we develop with).

Why. Nobody develops this repository with Codex or Antigravity, and keeping their files costs a parity check, a gate (the 32 KiB AGENTS.md chain was Codex's project_doc_max_bytes) and a table row each. OpenCode and Copilot CLI are used and had no subagents: the coordinator on those clients ran the whole workflow inline, which is what the subagents exist to avoid. Pinning every client to a Claude model keeps the implementer, the reviewers and the reader comparable across clients, so a finding or a report means the same thing whichever client produced it. Reading a CI log or a release note is the expensive, judgement-free part of two procedures; on Haiku the coordinator pays for a digest instead of a log.

Alternatives rejected. - Keeping Codex and Antigravity as development clients: unused, and each costs a file per agent plus gates that only they need. - Two readers, one for CI and one for release notes: both jobs are "read a lot, return a little", and every agent costs one file on each client. - The reviewers on Haiku as well: a weaker reviewer misses defects that then cost a stronger model's time. - No model pin on OpenCode and Copilot CLI: they would run on whatever the session picked, and the parity of the four clients would stop at the body.

Consequences. - OpenCode does not load .claude/agents/: its project agents are .opencode/agents/ (opencode debug agents lists them). Copilot CLI loads .github/agents/ only once the folder is trusted, and honours the model key: a model the subscription does not offer falls back to auto with a warning. Kiro's model list depends on the subscription in the same way. The repository keeps the pins; a developer's subscription is not its concern. - The spawn tool differs per client and lives in the per-client tables of the skills: OpenCode 2.0.30 delegates with its subagent tool (agent: <name>), Copilot CLI with task (agent_type: <name>). - A new agent is four files, one per client; the parity test fails until they agree.