1package provider
2
3import (
4 "encoding/json"
5 "os"
6)
7
8// UserModelsFile is the JSON format for user-defined models.
9// Place a models.json in $ZOT_HOME to add models that aren't in the
10// baked-in catalog or to override catalog entries.
11//
12// Example:
13//
14// {
15// "providers": {
16// "openai": {
17// "models": [
18// {
19// "id": "gpt-5.5",
20// "name": "GPT-5.5",
21// "reasoning": true,
22// "contextWindow": 400000,
23// "maxTokens": 128000,
24// "priceInput": 2.50,
25// "priceOutput": 15.00,
26// "priceCacheRead": 0.25
27// }
28// ]
29// }
30// }
31// }
32type UserModelsFile struct {
33 Providers map[string]UserProvider `json:"providers"`
34}
35
36// UserProvider groups models under a provider key.
37type UserProvider struct {
38 Models []UserModel `json:"models"`
39}
40
41// UserModel is a single model entry in the user's models.json.
42type UserModel struct {
43 ID string `json:"id"`
44 Name string `json:"name"`
45 Reasoning bool `json:"reasoning"`
46 ContextWindow int `json:"contextWindow"`
47 MaxTokens int `json:"maxTokens"`
48 PriceInput float64 `json:"priceInput"`
49 PriceOutput float64 `json:"priceOutput"`
50 PriceCacheRead float64 `json:"priceCacheRead"`
51 PriceCacheWrite float64 `json:"priceCacheWrite"`
52 Input []string `json:"input"` // informational only
53 API string `json:"api"` // informational only
54}
55
56// LoadUserModels reads a models.json file and returns the models
57// converted to the internal Model type. Returns nil on any error
58// (missing file, bad JSON, etc.) so the caller can treat it as
59// optional without error handling.
60func LoadUserModels(path string) []Model {
61 data, err := os.ReadFile(path)
62 if err != nil {
63 return nil
64 }
65 var file UserModelsFile
66 if err := json.Unmarshal(data, &file); err != nil {
67 return nil
68 }
69
70 var out []Model
71 for providerName, prov := range file.Providers {
72 // Normalize provider name: strip suffixes like "-codex" so
73 // "openai-codex" maps to "openai".
74 normalized := providerName
75 switch providerName {
76 case "openai-codex", "openai-responses":
77 normalized = "openai"
78 case "anthropic-messages":
79 normalized = "anthropic"
80 }
81
82 for _, um := range prov.Models {
83 m := Model{
84 Provider: normalized,
85 ID: um.ID,
86 DisplayName: um.Name,
87 ContextWindow: um.ContextWindow,
88 MaxOutput: um.MaxTokens,
89 Reasoning: um.Reasoning,
90 PriceInput: um.PriceInput,
91 PriceOutput: um.PriceOutput,
92 PriceCacheRead: um.PriceCacheRead,
93 PriceCacheWrite: um.PriceCacheWrite,
94 Source: "user",
95 }
96 if m.DisplayName == "" {
97 m.DisplayName = m.ID
98 }
99 out = append(out, m)
100 }
101 }
102 return out
103}
104
105// SetUserModels merges user-defined models into the active catalog.
106// User models take precedence over both the baked-in catalog and
107// live-discovered models.
108func SetUserModels(models []Model) {
109 if len(models) == 0 {
110 return
111 }
112 activeMu.Lock()
113 defer activeMu.Unlock()
114
115 // Build index of current active models.
116 byKey := func(p, id string) string { return p + "/" + id }
117 index := make(map[string]int, len(active))
118 for i, m := range active {
119 index[byKey(m.Provider, m.ID)] = i
120 }
121
122 for _, um := range models {
123 k := byKey(um.Provider, um.ID)
124 if idx, ok := index[k]; ok {
125 // Override existing entry but keep prices from user if
126 // they provided them, otherwise keep catalog prices.
127 existing := active[idx]
128 if um.PriceInput > 0 {
129 existing.PriceInput = um.PriceInput
130 }
131 if um.PriceOutput > 0 {
132 existing.PriceOutput = um.PriceOutput
133 }
134 if um.PriceCacheRead > 0 {
135 existing.PriceCacheRead = um.PriceCacheRead
136 }
137 if um.PriceCacheWrite > 0 {
138 existing.PriceCacheWrite = um.PriceCacheWrite
139 }
140 if um.DisplayName != "" {
141 existing.DisplayName = um.DisplayName
142 }
143 if um.ContextWindow > 0 {
144 existing.ContextWindow = um.ContextWindow
145 }
146 if um.MaxOutput > 0 {
147 existing.MaxOutput = um.MaxOutput
148 }
149 existing.Reasoning = um.Reasoning
150 existing.Source = "user"
151 existing.Speculative = false
152 active[idx] = existing
153 } else {
154 // New model not in catalog.
155 active = append(active, um)
156 }
157 }
158}