I1997 — The peer board can be read from the command line

○READY wave 0 · p1 · implementation profile · parallel safe

Part of development-runtime — The runtime has a development surface.

Objective

Project the peers capability onto the command line, so that a worker with no MCP tools can still ask who else is working in this repository and on which paths.

Why

On 2026-10-08 the owner told a session in prismatic-platform to 'use majordomus to find other instances / peers', and the tool had nothing to answer with: `majordomus peers` is an unknown command, and `session` describes one provider session of one checkout. Cross-session awareness exists only as the MCP tools majordomus_peers and majordomus_announce. From 2026-09-12 until 0.17.0 Claude Code dropped every majordomus_* tool in this repository, because two tools published an input schema with no root type, so for a month no session here could read or write the board either; eight sessions coordinated by direct messages instead. A reading that exists on one projection only is gone when that projection is.

Current state

peers.list and peers.announce are served over MCP and HTTP. The command line has no reading of the board; `majordomus context` prints a peers section only when the shell tool can reach the server and somebody else is attached.

Desired state

`majordomus peers` prints the board gathered across every checkout of the repository — each peer, its worktree, its claims, whether it is attached — with `--format json`, from the same capability the MCP tool projects. It says when a checkout's board could not be asked. In a repository with no layer or no server it says that, and exits with the code for a missing artifact rather than 0.

Scope

• apps/majordomus-cli/src/capability/builtin/peers.rs
• apps/majordomus-cli/src/cli.rs
• docs/MCP.md
• test/cases

Dependencies

None. This issue is a root of the graph.

Acceptance criteria

• `majordomus peers` lists a peer announced over MCP by another client of the same repository, with its worktree and claimed paths
• The command is a projection of the registry's capability: no board logic is written a second time for the command line
• With no server running it reports that no board could be asked and does not exit 0

Validation

• bin/majordomus plan validate
• MJ_TEST_JOBS=4 bash test/run.sh <the case this issue adds>

Evidence required

• cli_peers_lists_an_mcp_peer_case
• cli_peers_without_server_case

Evidence

None recorded. Every token above needs a command or an artifact behind it before this issue can be completed; narrative is refused.

Timeline

started

—

verified

—

completed

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Those three fields, the evidence above and the state of the dependencies are all the status is made of. There is no status field to disagree with them.

Canonical record: .ai/repo/project/issues/I1997.yaml. Read it back with majordomus plan show I1997.