Add agent library

Signed-off-by: Bryan Frimin <bryan@getprobo.com>

pkg/agent/schema.go

@@ -0,0 +1,84 @@
+// Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+package agent
+
+import (
+	"encoding/json"
+	"fmt"
+	"reflect"
+
+	"github.com/google/jsonschema-go/jsonschema"
+)
+
+func jsonSchemaFor[T any]() json.RawMessage {
+	t := reflect.TypeFor[T]()
+
+	schema, err := jsonschema.ForType(t, nil)
+	if err != nil {
+		panic(fmt.Sprintf("cannot generate schema for %s: %v", t, err))
+	}
+
+	stripNullTypes(schema)
+
+	data, err := json.Marshal(schema)
+	if err != nil {
+		panic(fmt.Sprintf("cannot marshal schema for %s: %v", t, err))
+	}
+
+	return json.RawMessage(data)
+}
+
+// stripNullTypes removes "null" from union types produced by pointer fields
+// (e.g. ["null","string"] becomes "string") and clears integer bounds so that
+// LLM providers receive a clean schema without Go-specific type constraints.
+func stripNullTypes(s *jsonschema.Schema) {
+	if s == nil {
+		return
+	}
+
+	if len(s.Types) > 0 {
+		filtered := make([]string, 0, len(s.Types))
+		for _, t := range s.Types {
+			if t != "null" {
+				filtered = append(filtered, t)
+			}
+		}
+		if len(filtered) == 1 {
+			s.Type = filtered[0]
+			s.Types = nil
+		} else if len(filtered) > 1 {
+			s.Types = filtered
+		}
+	}
+
+	s.Minimum = nil
+	s.Maximum = nil
+
+	if s.Type == "object" && s.Properties == nil {
+		s.Properties = make(map[string]*jsonschema.Schema)
+	}
+
+	for _, prop := range s.Properties {
+		stripNullTypes(prop)
+	}
+
+	if s.Items != nil {
+		stripNullTypes(s.Items)
+	}
+
+	if s.AdditionalProperties != nil {
+		stripNullTypes(s.AdditionalProperties)
+	}
+}