docs(j5): define members, guests, grants and shared conversations

[Jacksondr5]

Problem

Shared server defined several people on one server and left open how anyone is brought in, what they can reach, and what happens when two people write to the same agent. Those were ruled on in the multi-player session (#509), and the rulings stay proposals until a definition carries them.

What changed

• features/shared-server.md is rewritten. It defines members and guests, grants (a person, a project or a thread, and a level), the two levels View and Collaborate, what a share promises and what it does not, the share link, and what a guest sees. AC1 to AC4 keep their numbers; AC5 to AC24 are new.
• features/shared-conversations.md is new. It defines a thread more than one person can write to: the author named on each message, the note the agent gets about members and guests, asking in the conversation, guests queueing while members steer, how other people's messages render, and history.
• The glossary gains member, guest, grant, View, Collaborate, share link and shared conversation. The inbox definition says a guest has none (AC14). The overview row mentions guests.

Four things in the draft were not ruled on in the session and need a decision in review:

• where a person holds two grants covering the same thread, the higher level applies (Shared server AC7);
• the agent is told when a collaborator is added to or removed from an already shared thread (Shared conversations AC4);
• a guest is not offered to agents as someone who can be asked (Inbox AC14);
• Shared server AC3 now reads "member" where it read "person".

Shared conversations AC12 (a guest edits and removes their own queued messages) is tentative, as its History line says.

Left out on purpose: the per-person read marker and the catch-up summary, which are a separate feature; and entries in the register of divergences, which are owed when share links are built.

Nothing is built. The History lines link the session record that #509 adds, so #509 merges first.

Checklist

• One concern: the description has no "also"
• Tests cover the changed behavior (backend changes ship with focused tests): docs only, no behavior changes
• UI changes: before/after screenshots above, and a video for motion or interaction: no UI changes
• Upstream-owned files: each one is recorded in FORK.md (case text and file-table row) in this PR: none edited
• Upstream product: any change to what upstream's product does has a human decision linked above and a register entry in docs/j5/product/upstream.md: nothing changes yet; the register entries are owed by the PRs that build share links
• Surfaces: entry points, clients, providers, contracts, reverse states, connection modes (see AGENTS.md): docs only
• Docs: definitions under docs/j5/product/ and user docs rewritten where this changes them

Opus 5.5, Claude Code in J5 Code.

🤖 Generated with Claude Code

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated
j5-code	Ready	Preview	Oct 11, 2026 3:52am UTC