| 1 | package provider |
| 2 | |
| 3 | // Context window accounting for local admission. Unknown never assumes a |
| 4 | // shared prompt+completion window; Independent disables shared-window clipping. |
| 5 | type ContextWindowMode uint8 |
| 6 | |
| 7 | const ( |
| 8 | ContextWindowUnknown ContextWindowMode = iota |
| 9 | ContextWindowShared |
| 10 | ContextWindowIndependent |
| 11 | ) |
| 12 | |
| 13 | // How a provider places an output ceiling on the wire. |
| 14 | type OutputLimitMode uint8 |
| 15 | |
| 16 | const ( |
| 17 | OutputLimitOmitWhenSafe OutputLimitMode = iota |
| 18 | OutputLimitAlways |
| 19 | OutputLimitRequired |
| 20 | OutputLimitUnsupported |
| 21 | ) |
| 22 | |
| 23 | // ContextBudgetPolicy is the provider-owned window and output-limit contract. |
| 24 | // Zero Auto/Max means the value is unknown. It never feeds compact_ratio. |
| 25 | type ContextBudgetPolicy struct { |
| 26 | WindowMode ContextWindowMode |
| 27 | AutoOutputTokens int |
| 28 | MaxOutputTokens int |
| 29 | LimitMode OutputLimitMode |
| 30 | } |
| 31 | |
| 32 | // ContextBudgetPolicyProvider reports the unified budget contract. Existing |
| 33 | // OutputBudgetProvider and SharedWindowOutputProvider implementations remain |
| 34 | // valid fallbacks through ResolveContextBudgetPolicy. |
| 35 | type ContextBudgetPolicyProvider interface { |
| 36 | ContextBudgetPolicy() ContextBudgetPolicy |
| 37 | } |
| 38 | |
| 39 | const ( |
| 40 | ContextBudgetSourceUnknown = "unknown" |
| 41 | ContextBudgetSourceExplicit = "explicit" |
| 42 | ContextBudgetSourceOfficial = "official" |
| 43 | ContextBudgetSourceOpenCode = "opencode" |
| 44 | ContextBudgetSourceLearned = "learned" |
| 45 | ) |
| 46 | |
| 47 | func (m ContextWindowMode) String() string { |
| 48 | switch m { |
| 49 | case ContextWindowShared: |
| 50 | return "shared" |
| 51 | case ContextWindowIndependent: |
| 52 | return "independent" |
| 53 | default: |
| 54 | return "unknown" |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | func (m OutputLimitMode) String() string { |
| 59 | switch m { |
| 60 | case OutputLimitAlways: |
| 61 | return "always" |
| 62 | case OutputLimitRequired: |
| 63 | return "required" |
| 64 | case OutputLimitUnsupported: |
| 65 | return "unsupported" |
| 66 | default: |
| 67 | return "omit_when_safe" |
| 68 | } |
| 69 | } |
| 70 | |
| 71 | // ResolveContextBudgetPolicy prefers the new capability and otherwise maps the |
| 72 | // older output-budget interfaces so tests, fork wrappers, and unmigrated |
| 73 | // adapters keep working. |
| 74 | func ResolveContextBudgetPolicy(p Provider) ContextBudgetPolicy { |
| 75 | if p == nil { |
| 76 | return ContextBudgetPolicy{} |
| 77 | } |
| 78 | if owned, ok := p.(ContextBudgetPolicyProvider); ok { |
| 79 | return owned.ContextBudgetPolicy() |
| 80 | } |
| 81 | policy := ContextBudgetPolicy{WindowMode: ContextWindowUnknown, LimitMode: OutputLimitOmitWhenSafe} |
| 82 | if shared, ok := p.(SharedWindowOutputProvider); ok && shared.SharesContextWindow() { |
| 83 | policy.WindowMode = ContextWindowShared |
| 84 | } |
| 85 | if budget, ok := p.(OutputBudgetProvider); ok { |
| 86 | n := budget.OutputBudget() |
| 87 | if n > 0 { |
| 88 | policy.AutoOutputTokens = n |
| 89 | policy.MaxOutputTokens = n |
| 90 | if policy.WindowMode == ContextWindowShared { |
| 91 | policy.LimitMode = OutputLimitAlways |
| 92 | } |
| 93 | } |
| 94 | } |
| 95 | return policy |
| 96 | } |
| 97 |