[Pleximus29]

Summary

In a channel, the 0.X desktop @-mention picker offered agents that are not on that channel's roster. One cause is that locally managed agents always pass getMentionableAgentPubkeys. This change filters the final candidate list in buildMentionCandidates to !isAgent || isMember when mentionChannelId is set. People, and the case with no channel, are unchanged. This is a 0.X bug fix, not feature work.

Related issue

Fixes #9521

Testing

• New test, "in a channel, agents outside its roster are not offered", covering managed and relay agents. On main without the fix it fails: expected [Ada, Xenophon], got [Ada, Argus, Fizz, Scout, Xenophon].
• With the fix, the desktop unit suite (src/**/*.test.mjs, scripts/*.test.mjs) passes 6,972 of 6,972.
• We have run the same change in our own desktop build since 2026-10-31.
• No screenshots: this is a logic-only filter, and the behaviour is fully covered by the unit test.
• Not run locally: Biome, because of a local config/version mismatch, and the jsdom tests.

🤖 Generated with Claude Code

[github-actions]

🔐 Codex Security Review

Status: review required for the current range.

The current range is 69742376a9b1b15da62295f54a053913540722c1...23846d5e48003967d6d54107e343222a35d3ea06.
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[joahg]

🤖 The filter looks right to me: in a channel, agents need isMember to be offered, while people and the no-channel case (DM/new message) are unchanged, and the two new tests cover both sides.

Leaving this as a comment rather than an approval because it changes what users see in the desktop mention picker. It needs a sign-off from a design or core-team reviewer, especially on whether hiding non-member agents is the intended behavior. Today, mentioning an agent that isn't in the channel is one way people discover they need to add it, so it may be worth confirming whether that path should get a hint instead of disappearing entirely.

Nit: the new comment ("In a channel, only agents on its roster are offered.") restates the condition right below it and could be dropped.

[Pleximus29]

Thanks. I've dropped the comment in 23846d5.

On hiding versus a hint: for us, hiding is the intended behaviour. Some agents in our community are private to one person. A "not in this channel, add it?" hint would point other members at an agent they aren't meant to know about, while hiding reveals nothing. The no-channel case (DM / New Message) is unchanged.

To be clear, hiding in the picker isn't a privacy boundary. We checked with a fresh member in no channels. It could still list every agent's kind:0 profile and every kind:30177 record (owner and allowlist) straight from the relay. I filed that separately as #9528. This PR only makes the channel picker match what the channel can actually reach.

[joahg]

🤖 Thanks. The only change since my last pass is dropping the comment, and the filter logic is the same.

Your reasoning on hiding makes sense: a hint would leak the existence of private agents, and it's good that #9528 tracks the relay-side listing, since the picker isn't a privacy boundary. I don't have further findings. I'm still leaving this as a comment rather than an approval, because desktop mention-picker behavior needs sign-off from a design or core-team reviewer.