anthropic thinking

1 files changed, 167 insertions, 9 deletions

diff --git a/src/models_toml.zig b/src/models_toml.zig
index 2e2a920..9d64cb9 100644
--- a/src/models_toml.zig
+++ b/src/models_toml.zig
@@ -9,15 +9,27 @@
 //!
 //!     [<provider>.<alias>]
 //!     model       = <string>  # wire model id; defaults to <alias> if omitted
-//!     reasoning   = <string>  # default | off | minimal | low | medium | high
 //!     max_tokens  = <int>     # per-request output token cap
-//!     api_version = <string>  # anthropic_messages only
 //!     # pricing (all optional; USD per million tokens):
 //!     input       = <float>
 //!     output      = <float>
 //!     cache_read  = <float>
 //!     cache_write = <float>
 //!
+//!     # openai_chat-only knobs:
+//!     reasoning   = <string>  # default | off | minimal | low | medium | high
+//!
+//!     # anthropic_messages-only knobs:
+//!     api_version          = <string>  # Anthropic-Version header; default "2023-06-01"
+//!     thinking             = <string>  # disabled | enabled | adaptive  (default: enabled)
+//!     effort               = <string>  # low | medium | high | xhigh | max  (default: medium)
+//!                                      # only used when thinking = "adaptive"
+//!     thinking_budget_tokens = <int>   # max reasoning tokens for thinking = "enabled"
+//!                                      # default: 32000; null falls back to max_tokens - 1
+//!                                      # ignored when thinking = "adaptive" or "disabled"
+//!     thinking_interleaved = <bool>    # send interleaved-thinking beta header (default: false)
+//!                                      # only honoured when thinking = "enabled"
+//!
 //! Pricing semantics are unchanged from the original models.toml: any
 //! omitted price field is "unknown" (null), not zero. Write `= 0`
 //! explicitly to declare a known-zero rate.
@@ -25,13 +37,19 @@
 //! Example:
 //!
 //!     [anthropic.sonnet]
-//!     model       = "claude-sonnet-4-20250514"
-//!     reasoning   = "high"
-//!     max_tokens  = 8192
-//!     input       = 3.0
-//!     output      = 15.0
-//!     cache_read  = 0.3
-//!     cache_write = 3.75
+//!     model                  = "claude-sonnet-4-20250514"
+//!     max_tokens             = 8192
+//!     thinking               = "enabled"
+//!     thinking_budget_tokens = 16000
+//!     input                  = 3.0
+//!     output                 = 15.0
+//!     cache_read             = 0.3
+//!     cache_write            = 3.75
+//!
+//!     [anthropic.opus]
+//!     model    = "claude-opus-4-8"
+//!     thinking = "adaptive"
+//!     effort   = "high"
 //!
 //!     [openai.gpt]
 //!     model  = "gpt-4o"
@@ -55,6 +73,9 @@ pub const ReasoningEffort = panto.ReasoningEffort;
 
 /// A resolved model definition: the wire model id plus per-model knobs.
 /// Strings are owned by the `ModelRegistry`.
+pub const Thinking = panto.Thinking;
+pub const Effort = panto.Effort;
+
 pub const ModelDef = struct {
     /// `<provider_name>` — matches a `[providers.<name>]` in config.toml.
     provider: []const u8,
@@ -68,6 +89,14 @@ pub const ModelDef = struct {
     max_tokens: ?u32,
     /// anthropic_messages only; null = use the library default.
     api_version: ?[]const u8,
+    /// anthropic_messages only. Extended-thinking mode.
+    thinking: Thinking,
+    /// anthropic_messages only. Effort level for adaptive thinking.
+    effort: Effort,
+    /// anthropic_messages only. Manual thinking token budget; null = max_tokens - 1.
+    thinking_budget_tokens: ?u32,
+    /// anthropic_messages only. Whether to send the interleaved-thinking beta header.
+    thinking_interleaved: bool,
 };
 
 /// In-memory map of `(provider, alias) -> ModelDef`. Owns all strings.
@@ -239,6 +268,40 @@ fn ingestModel(
         break :blk null;
     };
 
+    const thinking: Thinking = blk: {
+        if (v.get("thinking")) |t| {
+            if (t.asString()) |s| {
+                break :blk std.meta.stringToEnum(Thinking, s) orelse .enabled;
+            }
+        }
+        break :blk .enabled;
+    };
+
+    const effort: Effort = blk: {
+        if (v.get("effort")) |e| {
+            if (e.asString()) |s| {
+                break :blk std.meta.stringToEnum(Effort, s) orelse .medium;
+            }
+        }
+        break :blk .medium;
+    };
+
+    const thinking_budget_tokens: ?u32 = blk: {
+        if (v.get("thinking_budget_tokens")) |bt| {
+            if (bt.asI64()) |i| {
+                if (i > 0) break :blk @intCast(i);
+            }
+        }
+        break :blk null;
+    };
+
+    const thinking_interleaved: bool = blk: {
+        if (v.get("thinking_interleaved")) |ti| {
+            if (ti.asBool()) |b| break :blk b;
+        }
+        break :blk false;
+    };
+
     // Own all the strings.
     const provider_copy = try alloc.dupe(u8, provider);
     errdefer alloc.free(provider_copy);
@@ -256,6 +319,10 @@ fn ingestModel(
         .reasoning = reasoning,
         .max_tokens = max_tokens,
         .api_version = api_version_copy,
+        .thinking = thinking,
+        .effort = effort,
+        .thinking_budget_tokens = thinking_budget_tokens,
+        .thinking_interleaved = thinking_interleaved,
     });
 
     // Pricing keys on the *wire* model id so usage records (which carry
@@ -420,3 +487,94 @@ test "configPath: falls back to HOME/.config" {
     defer a.free(got);
     try testing.expectEqualStrings("/home/user/.config/panto/models.toml", got);
 }
+
+test "parseInto: anthropic thinking fields parse correctly" {
+    var models = emptyModels(testing.allocator);
+    defer models.deinit();
+
+    const src =
+        \\[anthropic.sonnet]
+        \\model                  = "claude-sonnet-4-6"
+        \\thinking               = "enabled"
+        \\thinking_budget_tokens = 16000
+        \\thinking_interleaved   = true
+    ;
+    try parseInto(&models, src);
+
+    const def = models.defs.get("anthropic", "sonnet").?;
+    try testing.expectEqual(Thinking.enabled, def.thinking);
+    try testing.expectEqual(Effort.medium, def.effort); // default
+    try testing.expectEqual(@as(?u32, 16000), def.thinking_budget_tokens);
+    try testing.expectEqual(true, def.thinking_interleaved);
+}
+
+test "parseInto: anthropic adaptive thinking with effort" {
+    var models = emptyModels(testing.allocator);
+    defer models.deinit();
+
+    const src =
+        \\[anthropic.opus]
+        \\model    = "claude-opus-4-8"
+        \\thinking = "adaptive"
+        \\effort   = "high"
+    ;
+    try parseInto(&models, src);
+
+    const def = models.defs.get("anthropic", "opus").?;
+    try testing.expectEqual(Thinking.adaptive, def.thinking);
+    try testing.expectEqual(Effort.high, def.effort);
+    try testing.expectEqual(@as(?u32, null), def.thinking_budget_tokens); // absent => null
+    try testing.expectEqual(false, def.thinking_interleaved); // default
+}
+
+test "parseInto: anthropic thinking disabled" {
+    var models = emptyModels(testing.allocator);
+    defer models.deinit();
+
+    const src =
+        \\[anthropic.haiku]
+        \\model    = "claude-haiku-4-5-20251001"
+        \\thinking = "disabled"
+    ;
+    try parseInto(&models, src);
+
+    const def = models.defs.get("anthropic", "haiku").?;
+    try testing.expectEqual(Thinking.disabled, def.thinking);
+}
+
+test "parseInto: anthropic thinking defaults when absent" {
+    var models = emptyModels(testing.allocator);
+    defer models.deinit();
+
+    const src =
+        \\[anthropic.base]
+        \\model = "claude-sonnet-4-20250514"
+    ;
+    try parseInto(&models, src);
+
+    const def = models.defs.get("anthropic", "base").?;
+    try testing.expectEqual(Thinking.enabled, def.thinking);
+    try testing.expectEqual(Effort.medium, def.effort);
+    try testing.expectEqual(@as(?u32, null), def.thinking_budget_tokens);
+    try testing.expectEqual(false, def.thinking_interleaved);
+}
+
+test "parseInto: effort xhigh and max parse" {
+    var models = emptyModels(testing.allocator);
+    defer models.deinit();
+
+    const src =
+        \\[anthropic.opus-xhigh]
+        \\model    = "claude-opus-4-7"
+        \\thinking = "adaptive"
+        \\effort   = "xhigh"
+        \\[anthropic.opus-max]
+        \\model    = "claude-opus-4-6"
+        \\thinking = "adaptive"
+        \\effort   = "max"
+    ;
+    try parseInto(&models, src);
+
+    try testing.expectEqual(Effort.xhigh, models.defs.get("anthropic", "opus-xhigh").?.effort);
+    try testing.expectEqual(Effort.max, models.defs.get("anthropic", "opus-max").?.effort);
+}