1. 1//! Whether a capability is usable right now.
2. 2//!
3. 3//! Every capability is knowable offline: it is declared, or it has been
4. 4//! revoked. Nothing here talks to anything. An MCP server's connection state
5. 5//! — its catalog, its last failure, its retry backoff — belongs to the
6. 6//! on-demand pool (`vak_mcp::McpManager`), the one place a server is ever
7. 7//! started, and reaches the registry as declared data. The registry once
8. 8//! probed servers itself on a background timer, which meant spawning them
9. 9//! with nobody asking and re-spawning them after the pool had evicted them
10. 10//! for idleness.
11. 11
12. 12use serde::{Deserialize, Serialize};
13. 13
14. 14/// The lifecycle of one capability's usability.
15. 15#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
16. 16#[serde(tag = "state", rename_all = "kebab-case")]
17. 17pub enum Resolution {
18. 18 /// Declared and usable.
19. 19 Available,
20. 20 /// Revoked. Kept as a tombstone while a live epoch still references it,
21. 21 /// so a session mid-turn can still resolve what it was told about.
22. 22 Retired { reason: String },
23. 23}
24. 24
25. 25impl Resolution {
26. 26 /// Whether a turn may use this capability.
27. 27 pub fn is_usable(&self) -> bool {
28. 28 matches!(self, Resolution::Available)
29. 29 }
30. 30
31. 31 /// One-line status for the operator report and the model's standing
32. 32 /// section. Both read this, so they cannot disagree.
33. 33 pub fn summary(&self) -> String {
34. 34 match self {
35. 35 Resolution::Available => "ready".into(),
36. 36 Resolution::Retired { reason } => format!("removed: {reason}"),
37. 37 }
38. 38 }
39. 39}
40. 40