Agent allow-list not enforced correctly mid-session: presets enabled after session start are visible in agent_availability but rejected by call_agent

Bug report

Severity: warning
Category: code-bug
Service: chat / multi-agent

What happened

When a user enables agent presets mid-session via the chat HUD agent picker, the updated allow-list is injected into the next turn via the agent_availability system-reminder block — the newly enabled presets appear with their preset IDs and descriptions. However, calling call_agent with those preset IDs fails with:

Error: preset "<id>" is not allow-listed for this project. Run list_agents to see available ids, or ask the user to enable it from the chat HUD agent picker.

Additionally, list_agents returns an empty list throughout the same session, even after multiple turns following the user enabling presets.

Steps to reproduce

1. Start a new chat with no agent presets allow-listed for the project.
2. During the chat, the user enables one or more presets via the HUD agent picker.
3. On the next turn, agent_availability injection correctly shows the newly enabled presets with their IDs.
4. Call list_agents — returns empty.
5. Call call_agent with a preset ID from the agent_availability injection — returns the error above.

Expected behaviour

Presets enabled mid-session should become callable via call_agent in the same session. At minimum, list_agents should reflect the current allow-list state.

Actual behaviour

list_agents returns empty. call_agent rejects the preset as not allow-listed. The agent_availability injection and the runtime enforcement are out of sync.

Workaround

Starting a fresh chat after enabling presets resolves the issue — the allow-list is read correctly at session start.

Context

• Session: project "memory" (/storage/projects/memory)
• Presets affected: Board Curator (jn7a9c2fmr2f09v5vv35v8csn5868h4v), Wiki Curator (jn77bt8qmw81jjs9d9yx9kjd0s868b4h)
• The agent_availability injection listed 23 presets correctly; list_agents returned 0; call_agent rejected all of them
• Date: 2026-05-10

Additional note

The report_issue tool specified in the system prompt for bug reporting is not registered in this environment (not found in deferred tool list). Filing via GitHub as fallback.