lean_ctx/core/
server_capabilities.rs

1//! `GET /v1/capabilities` — runtime discovery of what this lean-ctx instance
2//! supports, so any client (any language) can branch on real features instead
3//! of trial calls. The HTTP route lives in `http_server`; the payload builder
4//! lives here so it stays compiled (and drift-tested) without the
5//! `http-server` feature.
6//!
7//! Contract: `docs/contracts/capabilities-contract-v1.md`. The set of
8//! [`TOP_LEVEL_KEYS`] is the stable contract surface and is bound to that doc
9//! by `tests/capabilities_contract_up_to_date.rs`.
10//!
11//! Not to be confused with [`crate::core::capabilities`], which models RBAC
12//! permissions (`fs:read`, …). This module describes *server* capabilities.
13
14use serde_json::{Value, json};
15
16use crate::core::contracts::{CAPABILITIES_CONTRACT_VERSION, status_kv, versions_kv};
17
18/// Stable, documented top-level keys of the capabilities document.
19pub const TOP_LEVEL_KEYS: [&str; 11] = [
20    "contract_version",
21    "server",
22    "plane",
23    "transports",
24    "presets",
25    "read_modes",
26    "tools",
27    "features",
28    "extensions",
29    "contracts",
30    "contract_status",
31];
32
33/// Build the capabilities document for this running instance.
34pub fn capabilities_value() -> Value {
35    let manifest = crate::core::mcp_manifest::manifest_value();
36    let tool_names = tool_names(&manifest);
37    let read_modes = manifest.get("read_modes").cloned().unwrap_or(Value::Null);
38    let active_persona =
39        crate::core::persona::Persona::resolve(&crate::core::config::Config::load());
40
41    json!({
42        "contract_version": CAPABILITIES_CONTRACT_VERSION,
43        "server": {
44            "name": "lean-ctx",
45            "version": env!("CARGO_PKG_VERSION"),
46            "persona": active_persona.name,
47        },
48        "plane": "personal",
49        "transports": ["stdio-mcp", "http-mcp", "rest", "sse"],
50        "presets": crate::core::persona::Persona::builtin_names(),
51        "read_modes": read_modes,
52        "tools": {
53            "total": tool_names.len(),
54            "names": tool_names,
55        },
56        "features": features(),
57        "extensions": extensions(),
58        "contracts": versions_kv(),
59        // Stability per contract document (frozen|stable|experimental) so
60        // clients can check compatibility before building against a surface
61        // (GL #394). Additive: existing consumers are unaffected.
62        "contract_status": status_kv(),
63    })
64}
65
66fn tool_names(manifest: &Value) -> Vec<String> {
67    manifest
68        .get("tools")
69        .and_then(|t| t.get("granular"))
70        .and_then(|g| g.as_array())
71        .map(|arr| {
72            arr.iter()
73                .filter_map(|t| t.get("name").and_then(|n| n.as_str()).map(String::from))
74                .collect()
75        })
76        .unwrap_or_default()
77}
78
79/// Always-on Community capabilities. They are explicit Trust Core product
80/// records rather than capabilities inferred to be free because they are local.
81pub const COMMUNITY_ALWAYS_ON_FEATURES: &[&str] = &[
82    "compression",
83    "caching",
84    "knowledge",
85    "session",
86    "gateway",
87    "sensitivity_floor",
88    "savings_ledger",
89    "audit_trail",
90    "routing",
91    "team_seat_value_v1",
92];
93
94/// Community capabilities gated only by compilation.
95pub const COMMUNITY_OPTIONAL_FEATURES: &[&str] = &[
96    "ast_compression",
97    "semantic_search",
98    "http_server",
99    "wasm_runtime",
100    // Cross-shape routing Anthropic→OpenAI (enterprise#16, `shape-xlat`).
101    "shape_translation",
102];
103
104/// Always-on capabilities plus compiled-in feature flags. Booleans reflect what
105/// this binary can actually do.
106fn features() -> Value {
107    json!({
108        "compression": true,
109        "caching": true,
110        "knowledge": true,
111        "session": true,
112        "gateway": true,
113        "sensitivity_floor": true,
114        "savings_ledger": true,
115        "audit_trail": true,
116        // The advertised primitive is deterministic Community routing.
117        // Personalized adaptive routing has its own Pro capability ID.
118        "routing": true,
119        "team_seat_value_v1": true,
120        "ast_compression": cfg!(feature = "tree-sitter"),
121        "semantic_search": cfg!(feature = "embeddings"),
122        "http_server": cfg!(feature = "http-server"),
123        "wasm_runtime": cfg!(feature = "wasm"),
124        "shape_translation": cfg!(feature = "shape-xlat"),
125    })
126}
127
128/// Runtime-discovered extensions: installed plugins plus the registered
129/// read-modes / compressors / chunkers (EPIC 12.9). The sandboxed extension
130/// runtime (EPIC 12.8) expands what registers here.
131fn extensions() -> Value {
132    let (read_modes, compressors, chunkers) = crate::core::extension_registry::global()
133        .read()
134        .map(|r| (r.read_mode_names(), r.compressor_names(), r.chunker_names()))
135        .unwrap_or_default();
136
137    json!({
138        "plugins": [],
139        "tools": [],
140        "read_modes": read_modes,
141        "compressors": compressors,
142        "chunkers": chunkers,
143    })
144}
145
146#[cfg(test)]
147mod tests {
148    use super::*;
149
150    #[test]
151    fn payload_has_exactly_documented_top_level_keys() {
152        let v = capabilities_value();
153        let obj = v.as_object().expect("capabilities is an object");
154        let mut keys: Vec<&str> = obj.keys().map(String::as_str).collect();
155        keys.sort_unstable();
156        let mut expected: Vec<&str> = TOP_LEVEL_KEYS.to_vec();
157        expected.sort_unstable();
158        assert_eq!(keys, expected, "top-level keys drifted from TOP_LEVEL_KEYS");
159    }
160
161    #[test]
162    fn contract_version_matches_constant() {
163        let v = capabilities_value();
164        assert_eq!(v["contract_version"], json!(CAPABILITIES_CONTRACT_VERSION));
165    }
166
167    #[test]
168    fn extensions_expose_registry_builtins() {
169        let v = capabilities_value();
170        let ext = &v["extensions"];
171        assert!(ext["plugins"].is_array());
172        let compressors = ext["compressors"].as_array().expect("compressors array");
173        assert!(compressors.iter().any(|c| c == "identity"));
174        assert!(
175            ext["read_modes"]
176                .as_array()
177                .is_some_and(|a| a.iter().any(|m| m == "full"))
178        );
179        assert!(
180            ext["chunkers"]
181                .as_array()
182                .is_some_and(|a| a.iter().any(|c| c == "lines"))
183        );
184    }
185
186    #[test]
187    fn every_advertised_feature_has_an_explicit_product_record() {
188        let v = capabilities_value();
189        for key in v["features"].as_object().expect("features object").keys() {
190            assert!(
191                crate::core::product_capabilities::registry()
192                    .find(key)
193                    .is_some(),
194                "server feature '{key}' lacks product classification"
195            );
196        }
197    }
198
199    #[test]
200    fn community_always_on_features_are_available_without_an_account() {
201        let v = capabilities_value();
202        for key in COMMUNITY_ALWAYS_ON_FEATURES {
203            assert_eq!(
204                v["features"][key],
205                json!(true),
206                "Community capability '{key}' must be available"
207            );
208            let capability = crate::core::product_capabilities::registry()
209                .find(key)
210                .expect("feature classified");
211            assert_eq!(
212                capability.minimum_plan(),
213                crate::core::product_capabilities::Plan::Community
214            );
215            assert!(!capability.account_required);
216        }
217    }
218
219    #[test]
220    fn reports_compiled_features() {
221        let v = capabilities_value();
222        // Always-on capabilities are unconditionally true.
223        assert_eq!(v["features"]["compression"], json!(true));
224        assert_eq!(v["features"]["savings_ledger"], json!(true));
225        assert_eq!(v["features"]["team_seat_value_v1"], json!(true));
226        assert_eq!(
227            v["contracts"]["leanctx.contract.team_seat_value_v1.schema_version"],
228            json!(1)
229        );
230        // Feature-gated flags mirror the compile-time cfg.
231        assert_eq!(
232            v["features"]["semantic_search"],
233            json!(cfg!(feature = "embeddings"))
234        );
235    }
236}
lean_ctx/core/server_capabilities.rs

lean_ctx/core/
server_capabilities.rs
