feat: v0.7.0 — AgentDef provider/model + install --provider/--model/--no-config : résolution flag > agent > défaut, erreur si provider inconnu (liste du registre), warning si modèle absent, résolution affichée en résumé et au --dry-run (closes #90)

- Providers réels livrés dans le catalogue par défaut (anthropic★/openai/deepseek/google) + hints provider sur claude-code/deepseek-harness - Suppression par null dans l'overlay : am providers remove écrit <nom>: null (merge traite null comme suppression, set_path remplace le null avant de descendre) - Cascade @secret (#89) : le provider déclaré de l'agent prime sur default_provider
2026-08-19 20:03:47 -04:00
parent 7312e6ceab
commit ebc753cc4a
14 changed files with 336 additions and 38 deletions
@@ -499,7 +499,7 @@ S'appuie sur #36 (secrets), #40 (profils), #71 (modèle), #66 (sync) — livrés
 |---|---|---|---|
 | [#88](https://git.dracodev.net/Projets/agent-manager/issues/88) | ✅ Registre de providers + commandes `am providers` (settings.providers, default_provider) | M | — |
 | [#89](https://git.dracodev.net/Projets/agent-manager/issues/89) | ✅ Secrets partagés par provider (namespace keyring + résolution `@secret` fallback) | S | #88 |
-| [#90](https://git.dracodev.net/Projets/agent-manager/issues/90) | AgentDef provider/model + flags `--provider/--model/--no-config` à l'install | M | #88 |
+| [#90](https://git.dracodev.net/Projets/agent-manager/issues/90) | ✅ AgentDef provider/model + flags `--provider/--model/--no-config` à l'install | M | #88 |
 | [#91](https://git.dracodev.net/Projets/agent-manager/issues/91) | Configuration post-install : bloc `config:` par agent (env_map + fichiers) | L | #89, #90 |
 | [#92](https://git.dracodev.net/Projets/agent-manager/issues/92) | `am run/start --provider` : override au lancement (providers cloud inclus) | M | #90 |

@@ -45,18 +45,28 @@ settings:
  # sync_on_exit: true          # pousse automatiquement à la fermeture du REPL (opt-in)
  # Registre des providers LLM (#88) : nom -> base_url, modèles, modèle par
  # défaut. Le provider par défaut est utilisé à l'install/au run quand aucun
-  # n'est donné. Les tokens ne vont JAMAIS ici — ils vivent dans le keyring OS
-  # sous providers/<nom>/api_key (issue #89, am providers set-token).
-  # default_provider: openai
-  # providers:
-  #   openai:
-  #     base_url: https://api.openai.com/v1
-  #     default_model: gpt-5.2
-  #     models: [gpt-5.2, gpt-5.1-mini, o4-mini]
-  #   deepseek:
-  #     base_url: https://api.deepseek.com
-  #     default_model: deepseek-chat
-  #     models: [deepseek-chat, deepseek-reasoner]
+  # n'est donné (issue #90). Les tokens ne vont JAMAIS ici — ils vivent dans
+  # le keyring OS sous providers/<nom>/api_key (issue #89, am providers set-token).
+  # Pour retirer un provider du catalogue par défaut : am providers remove <nom>
+  # (écrit "<nom>: null" dans votre config — le null supprime l'entrée au merge).
+  default_provider: anthropic
+  providers:
+    anthropic:
+      base_url: https://api.anthropic.com/v1
+      default_model: claude-sonnet-4-5
+      models: [claude-sonnet-4-5, claude-opus-4-1, claude-haiku-4-5]
+    openai:
+      base_url: https://api.openai.com/v1
+      default_model: gpt-5.2
+      models: [gpt-5.2, gpt-5.1-mini, o4-mini]
+    deepseek:
+      base_url: https://api.deepseek.com
+      default_model: deepseek-chat
+      models: [deepseek-chat, deepseek-reasoner]
+    google:
+      base_url: https://generativelanguage.googleapis.com/v1beta
+      default_model: gemini-2.5-pro
+      models: [gemini-2.5-pro, gemini-2.5-flash]

 # --- Command aliases ----------------------------------------------------------
 aliases:
@@ -92,6 +102,7 @@ agents:
    dependencies:
      - { name: node, min_version: "18.0.0", install_hint: "https://nodejs.org" }
    run: claude
+    provider: anthropic
    tags: [anthropic, assistant, source-available, mainstream]

  - name: deepseek-harness
@@ -105,6 +116,7 @@ agents:
    dependencies:
      - { name: node, min_version: "20.0.0", install_hint: "https://nodejs.org" }
    run: dsh
+    provider: deepseek
    tags: [deepseek, harness, multi-agent, plugins, web-ui]

  - name: hermes-agent
@@ -4,7 +4,7 @@
 .SH NAME
 install \- Install an agent and its dependencies
 .SH SYNOPSIS
-\fBinstall\fR [\fB\-\-method\fR] [\fB\-\-force\fR] [\fB\-h\fR|\fB\-\-help\fR] <\fIAGENT\fR> 
+\fBinstall\fR [\fB\-\-method\fR] [\fB\-\-force\fR] [\fB\-\-provider\fR] [\fB\-\-model\fR] [\fB\-\-no\-config\fR] [\fB\-h\fR|\fB\-\-help\fR] <\fIAGENT\fR> 
 .SH DESCRIPTION
 Install an agent and its dependencies
 .SH OPTIONS
@@ -15,6 +15,15 @@ Select the install method (index, or type: npm, pip, uv, cargo, go, bun, curl, b
 \fB\-\-force\fR
 Reinstall even if already installed
 .TP
+\fB\-\-provider\fR \fI<PROVIDER>\fR
+Provider to configure (default: the agent\*(Aqs provider, else settings.default_provider) (issue #90)
+.TP
+\fB\-\-model\fR \fI<MODEL>\fR
+Model to configure (default: the provider\*(Aqs default model) (issue #90)
+.TP
+\fB\-\-no\-config\fR
+Skip the post\-install provider configuration (issue #91)
+.TP
 \fB\-h\fR, \fB\-\-help\fR
 Print help
 .TP
@@ -359,6 +359,15 @@ pub enum Command {
        /// Reinstall even if already installed
        #[arg(long)]
        force: bool,
+        /// Provider to configure (default: the agent's provider, else settings.default_provider) (issue #90)
+        #[arg(long, value_name = "PROVIDER")]
+        provider: Option<String>,
+        /// Model to configure (default: the provider's default model) (issue #90)
+        #[arg(long, value_name = "MODEL")]
+        model: Option<String>,
+        /// Skip the post-install provider configuration (issue #91)
+        #[arg(long)]
+        no_config: bool,
    },
    /// Uninstall an agent (managed or external) and clean its files
    Uninstall {
@@ -8,7 +8,15 @@ use crate::runner::SystemRunner;
 use anyhow::{anyhow, bail, Result};
 use std::collections::BTreeMap;

-pub fn run(app: &App, agent_name: &str, method_sel: Option<&str>, force: bool) -> Result<i32> {
+pub fn run(
+    app: &App,
+    agent_name: &str,
+    method_sel: Option<&str>,
+    force: bool,
+    provider: Option<&str>,
+    model: Option<&str>,
+    no_config: bool,
+) -> Result<i32> {
    let agent = require_agent(app, agent_name)?;
    let runner = SystemRunner::new(app.dry_run(), app.cli.verbose, &app.log);

@@ -38,6 +46,20 @@ pub fn run(app: &App, agent_name: &str, method_sel: Option<&str>, force: bool) -
    let methods = spec.all_methods();
    let method = select_method(&methods, method_sel)?;

+    // Provider/model resolution (issue #90): flag > agent.provider >
+    // settings.default_provider ; flag --model > agent.model >
+    // provider.default_model. Displayed in the summary (and by --dry-run).
+    let resolved = resolve_provider_config(app, agent, provider, model)?;
+    if no_config {
+        app.log
+            .info(crate::i18n::tr("--no-config : aucune configuration post-install"));
+    } else if !spec.configurable {
+        app.log.info(&crate::tr_fmt!(
+            "{} ne prend aucune configuration (install.configurable: false)",
+            agent.name
+        ));
+    }
+
    // Already installed?
    let existing = app.state.get(&agent.name).ok().flatten();
    if existing.is_some() && !force && !app.dry_run() {
@@ -138,10 +160,17 @@ pub fn run(app: &App, agent_name: &str, method_sel: Option<&str>, force: bool) -
    let entry = installers::make_entry(agent, method, &outcome, app);
    let version = entry.version.clone().unwrap_or_else(|| "unknown".to_string());
    app.state.set(&entry)?;
+    let mut args = vec![format!("method={}", method.kind)];
+    if let Some((p, m)) = &resolved {
+        args.push(format!("provider={p}"));
+        if let Some(m) = m {
+            args.push(format!("model={m}"));
+        }
+    }
    app.emit(
        &Event::now(EventKind::Install)
            .with_agent(agent.name.clone())
-            .with_args(vec![format!("method={}", method.kind)]),
+            .with_args(args),
    );
    crate::hooks::run_hooks(
        app,
@@ -161,3 +190,84 @@ pub fn run(app: &App, agent_name: &str, method_sel: Option<&str>, force: bool) -
    }
    Ok(0)
 }
+
+/// Resolve the provider + model of this install (issue #90) and print what
+/// will be configured. Returns (provider, model) when resolved.
+///
+/// Validation rules:
+/// - an explicit `--provider` that is not registered → error listing the
+///   registry (the user asked for it by name);
+/// - an agent-declared provider that is not registered → warning only
+///   (catalog metadata may reference a provider the user has not added yet);
+/// - a model absent from the provider's model list → warning, not blocking.
+fn resolve_provider_config(
+    app: &App,
+    agent: &AgentDef,
+    flag_provider: Option<&str>,
+    flag_model: Option<&str>,
+) -> Result<Option<(String, Option<String>)>> {
+    let flag_p = flag_provider.filter(|p| !p.is_empty());
+    let agent_p = agent.provider.as_deref().filter(|p| !p.is_empty());
+
+    // Explicit provider requested but not registered: hard error.
+    if let Some(p) = flag_p {
+        if crate::providers::get(&app.config, p).is_none() {
+            let known = crate::providers::names(&app.config);
+            let hint = if known.is_empty() {
+                "am providers add <nom> --base-url <url>".to_string()
+            } else {
+                known.join(", ")
+            };
+            bail!(crate::tr_fmt!(
+                "provider '{}' inconnu — providers enregistrés: {}",
+                p,
+                hint
+            ));
+        }
+    }
+    // Agent-declared provider not registered: warn (unless the user already
+    // overrode it with --provider, which was validated above).
+    if let Some(p) = agent_p {
+        if flag_p.is_none() && crate::providers::get(&app.config, p).is_none() {
+            app.log.warn(&crate::tr_fmt!(
+                "provider '{}' (déclaré par {}) non enregistré — voir: am providers add {} --base-url <url>",
+                p,
+                agent.name,
+                p
+            ));
+            return Ok(None);
+        }
+    }
+
+    let Some((pname, def, model)) = crate::providers::resolve_for(
+        &app.config,
+        agent.provider.as_deref(),
+        agent.model.as_deref(),
+        flag_provider,
+        flag_model,
+    ) else {
+        app.log.info(crate::i18n::tr(
+            "aucun provider configuré — voir: am providers add <nom> --base-url <url>",
+        ));
+        return Ok(None);
+    };
+
+    // Model not in the provider's list: warn, keep going.
+    if let Some(m) = model {
+        if !def.models.is_empty() && !def.models.iter().any(|x| x == m) {
+            app.log.warn(&crate::tr_fmt!(
+                "modèle '{}' absent de la liste du provider '{}' — modèles: {}",
+                m,
+                pname,
+                def.models.join(", ")
+            ));
+        }
+    }
+    let model_label = model.unwrap_or("-");
+    app.log.info(&crate::tr_fmt!(
+        "configuré avec le provider {} (modèle {})",
+        pname,
+        model_label
+    ));
+    Ok(Some((pname.to_string(), model.map(String::from))))
+}
@@ -169,7 +169,18 @@ pub fn execute_command(app: &App, cmd: &Command) -> Result<i32> {
            agent,
            method,
            force,
-        } => install_cmd::run(app, agent, method.as_deref(), *force),
+            provider,
+            model,
+            no_config,
+        } => install_cmd::run(
+            app,
+            &agent,
+            method.as_deref(),
+            *force,
+            provider.as_deref(),
+            model.as_deref(),
+            *no_config,
+        ),
        Command::Uninstall { agent, purge } => uninstall_cmd::run(app, agent, *purge),
        Command::Update { agent, all, rollback } => {
            update_cmd::run(app, agent.as_deref(), *all, rollback.as_deref())
@@ -311,7 +322,10 @@ pub fn resolve_exec(
        crate::secrets::resolve_env_secrets(
            &crate::secrets::store(),
            &agent.name,
-            crate::providers::default_name(&app.config),
+            agent
+                .provider
+                .as_deref()
+                .or_else(|| crate::providers::default_name(&app.config)),
            &mut env,
        );
    for w in warnings {
@@ -38,15 +38,19 @@ pub fn run(app: &App, sub: Option<&ProvidersCmd>) -> Result<i32> {
 fn list(app: &App) -> Result<i32> {
    let providers = providers::all(&app.config);
    let default_name = providers::default_name(&app.config);
+    let defined: Vec<(&String, &ProviderDef)> = providers
+        .iter()
+        .filter_map(|(k, v)| v.as_ref().map(|def| (k, def)))
+        .collect();
    if app.json() {
-        let rows: Vec<serde_json::Value> = providers
+        let rows: Vec<serde_json::Value> = defined
            .iter()
            .map(|(name, def)| provider_json(name, def, default_name == Some(name.as_str())))
            .collect();
        print_json(&rows);
        return Ok(0);
    }
-    if providers.is_empty() {
+    if defined.is_empty() {
        app.log.info(&crate::i18n::tr(
            "aucun provider enregistré — voir: am providers add <nom> --base-url <url>",
        ));
@@ -58,7 +62,7 @@ fn list(app: &App) -> Result<i32> {
        "DÉFAUT",
        "MODÈLES",
    ]);
-    for (name, def) in providers {
+    for (name, def) in &defined {
        let star = if default_name == Some(name.as_str()) {
            "★"
        } else {
@@ -226,7 +230,14 @@ fn remove(app: &App, name: &str) -> Result<i32> {
    }
    let path = crate::commands::config_cmd::active_config_path(app)?;
    let mut root = read_yaml(&path)?;
-    remove_path(&mut root, &["settings", "providers", name])?;
+    // Write an explicit `null` instead of removing the key: the effective
+    // config is a merge (default catalog + user overlay) and a null marker
+    // is what actually deletes a provider shipped in the defaults (issue #90).
+    set_path(
+        &mut root,
+        &["settings", "providers", name],
+        serde_yaml::Value::Null,
+    )?;
    write_yaml(&path, &root)?;
    crate::commands::config_cmd::reload_and_validate(&path)?;
    app.emit(
@@ -297,7 +308,9 @@ fn write_yaml(path: &Path, root: &serde_yaml::Value) -> Result<()> {
        .map_err(|e| anyhow!("cannot write {}: {e}", path.display()))
 }

-/// Set a value at a dotted path, creating intermediate mappings.
+/// Set a value at a dotted path, creating intermediate mappings. A null
+/// value already present on the path (a provider deletion marker from
+/// `providers remove`, issue #90) is replaced by a fresh mapping.
 fn set_path(root: &mut serde_yaml::Value, parts: &[&str], value: serde_yaml::Value) -> Result<()> {
    let mut node = root
        .as_mapping_mut()
@@ -306,6 +319,9 @@ fn set_path(root: &mut serde_yaml::Value, parts: &[&str], value: serde_yaml::Val
        let entry = node
            .entry(serde_yaml::Value::String(part.to_string()))
            .or_insert_with(|| serde_yaml::Value::Mapping(Default::default()));
+        if entry.is_null() {
+            *entry = serde_yaml::Value::Mapping(Default::default());
+        }
        node = entry
            .as_mapping_mut()
            .ok_or_else(|| anyhow!("'{part}' is not a mapping — cannot descend into it"))?;
@@ -466,9 +482,11 @@ mod tests {
        p.probe_cache_file = dir.join("probe-cache.json");
        p.config_dir = Some(dir.join("config"));
        app.paths = p;
-        add(&app, "openai", "https://api.openai.com/v1", None, None).unwrap();
+        // "localai" is not shipped in the embedded default catalog, so its
+        // presence proves a real write happened.
+        add(&app, "localai", "http://127.0.0.1:8080/v1", None, None).unwrap();
        let cli2 = crate::cli::Cli::parse_from(["am", "--config", cfg.to_str().unwrap()]);
        let reloaded = App::from_cli(cli2).unwrap();
-        assert!(providers::get(&reloaded.config, "openai").is_none());
+        assert!(providers::get(&reloaded.config, "localai").is_none());
    }
 }
@@ -196,6 +196,8 @@ mod tests {
            pin_version: None,
            model_env: None,
            model_arg: None,
+            provider: None,
+            model: None,
            tags: tags.iter().map(|s| s.to_string()).collect(),
            installable: false,
            note: None,
@@ -148,7 +148,7 @@ pub struct Settings {
    /// they live in the OS keyring under `providers/<name>/api_key`
    /// (issue #89).
    #[serde(default)]
-    pub providers: Option<BTreeMap<String, ProviderDef>>,
+    pub providers: Option<BTreeMap<String, Option<ProviderDef>>>,
 }

 /// One entry of the LLM provider registry (issue #88).
@@ -275,7 +275,10 @@ impl Settings {

    /// Look up one provider of the registry (issue #88).
    pub fn provider(&self, name: &str) -> Option<&ProviderDef> {
-        self.providers.as_ref().and_then(|m| m.get(name))
+        self.providers
+            .as_ref()
+            .and_then(|m| m.get(name))
+            .and_then(|p| p.as_ref())
    }

    /// Name of the default provider (issue #88).
@@ -331,6 +334,14 @@ pub struct AgentDef {
    /// CLI flag carrying the model name at launch (issue #71, e.g. "--model").
    #[serde(default)]
    pub model_arg: Option<String>,
+    /// Preferred provider of this agent (issue #90, e.g. "anthropic" for
+    /// claude-code). Falls back to settings.default_provider when unset.
+    #[serde(default)]
+    pub provider: Option<String>,
+    /// Preferred model for this agent (issue #90). Falls back to the
+    /// provider's default_model when unset.
+    #[serde(default)]
+    pub model: Option<String>,
    #[serde(default)]
    pub tags: Vec<String>,
    /// When false, the agent is listed but cannot be installed locally.
@@ -588,6 +599,10 @@ pub struct InstallSpec {
    /// Commands executed after a successful install (PATH includes the bin dir).
    #[serde(default)]
    pub post_install: Vec<String>,
+    /// The agent accepts a post-install provider configuration (issue #91).
+    /// False for agents without any API (issue #90).
+    #[serde(default = "default_true")]
+    pub configurable: bool,
 }

 impl InstallSpec {
@@ -815,12 +830,21 @@ pub fn merge(base: &mut Config, overlay: Config) {
        s.default_provider = o.default_provider;
    }
    // Providers merge key by key (issue #88): an overlay adds or replaces
-    // one provider without wiping the others.
+    // one provider without wiping the others. An explicit `null` in the
+    // overlay DELETES the provider (the standard YAML overlay pattern) so a
+    // provider shipped in the default catalog can be removed by the user.
    if let Some(overlay_providers) = o.providers {
        match s.providers.as_mut() {
            Some(map) => {
                for (k, v) in overlay_providers {
-                    map.insert(k, v);
+                    match v {
+                        Some(def) => {
+                            map.insert(k, Some(def));
+                        }
+                        None => {
+                            map.remove(&k);
+                        }
+                    }
                }
            }
            None => s.providers = Some(overlay_providers),
@@ -900,6 +924,10 @@ pub fn validate(config: &Config) -> Vec<String> {
        }
        if let Some(providers) = &config.settings.providers {
            for (name, p) in providers {
+                // A null entry is a deletion marker (issue #90): skip it.
+                let Some(p) = p else {
+                    continue;
+                };
                if p.base_url.trim().is_empty() {
                    problems.push(format!("provider '{name}': 'base_url' is required"));
                }
@@ -797,11 +797,14 @@ pub static HELP_SPECS: &[HelpSpec] = &[
        name: "install",
        category: "Commands",
        usage: "install {flags} <agent>",
-        about: "Install an agent and its dependencies.",
-        search_terms: &["add", "setup"],
+        about: "Install an agent and its dependencies, and resolve its LLM provider + model (issue #90): --provider > agent.provider > settings.default_provider; --model > agent.model > provider.default_model.",
+        search_terms: &["add", "setup", "provider", "model"],
        flags: &[
            HelpFlag { short: "", long: "--method", value: "METHOD", desc: "Select the install method (index, or type: npm, pip, uv, cargo, go, bun, curl, binary, git)" },
            HelpFlag { short: "", long: "--force", value: "", desc: "Reinstall even if already installed" },
+            HelpFlag { short: "", long: "--provider", value: "PROVIDER", desc: "Provider to configure (default: the agent's provider, else settings.default_provider)" },
+            HelpFlag { short: "", long: "--model", value: "MODEL", desc: "Model to configure (default: the provider's default model)" },
+            HelpFlag { short: "", long: "--no-config", value: "", desc: "Skip the post-install provider configuration (issue #91)" },
        ],
        subcommands: &[],
        parameters: &[
@@ -812,6 +815,9 @@ pub static HELP_SPECS: &[HelpSpec] = &[
            HelpExample { desc: "Install an agent with its dependencies.", code: "install claude-code" },
            HelpExample { desc: "Pick a specific install method.", code: "install smelt --method uv" },
            HelpExample { desc: "Reinstall over an existing install.", code: "install claude-code --force" },
+            HelpExample { desc: "Force a provider and a model.", code: "install agentty --provider deepseek --model deepseek-reasoner" },
+            HelpExample { desc: "Preview the resolved provider/model without installing.", code: "install agentty --dry-run" },
+            HelpExample { desc: "Install without any post-install configuration.", code: "install agentty --no-config" },
        ],
    },
    HelpSpec {
@@ -178,6 +178,13 @@ pub const CATALOG: &[(&str, &str)] = &[
    ("secret '{}' stocké pour {}", "secret '{}' stored for {}"),
    ("secret '{}' supprimé pour {}", "secret '{}' removed for {}"),
    ("secret '{}' inexistant pour {}", "secret '{}' does not exist for {}"),
+    ("--no-config : aucune configuration post-install", "--no-config: no post-install configuration"),
+    ("{} ne prend aucune configuration (install.configurable: false)", "{} takes no configuration (install.configurable: false)"),
+    ("provider '{}' inconnu — providers enregistrés: {}", "unknown provider '{}' — registered providers: {}"),
+    ("provider '{}' (déclaré par {}) non enregistré — voir: am providers add {} --base-url <url>", "provider '{}' (declared by {}) is not registered — see: am providers add {} --base-url <url>"),
+    ("aucun provider configuré — voir: am providers add <nom> --base-url <url>", "no provider configured — see: am providers add <name> --base-url <url>"),
+    ("modèle '{}' absent de la liste du provider '{}' — modèles: {}", "model '{}' is not in provider '{}' model list — models: {}"),
+    ("configuré avec le provider {} (modèle {})", "configured with provider {} (model {})"),
    ("usage: secret set <nom> --agent <agent> --value <valeur> | secret set <nom> --provider <provider> --value <valeur>", "usage: secret set <name> --agent <agent> --value <value> | secret set <name> --provider <provider> --value <value>"),
    ("{} entrée(s) verrouillée(s) — suppression planifiée au prochain redémarrage", "{} locked entrie(s) — deletion scheduled for the next reboot"),
    ("{} entrée(s) verrouillée(s) — le processus différé les supprimera après la fermeture de am", "{} locked entrie(s) — the deferred process will delete them after am exits"),
@@ -10,13 +10,21 @@ use crate::config::{Config, ProviderDef};
 use std::collections::BTreeMap;

 /// Empty provider map shared by the helpers below (never mutated).
-static EMPTY: BTreeMap<String, ProviderDef> = BTreeMap::new();
+static EMPTY: BTreeMap<String, Option<ProviderDef>> = BTreeMap::new();

 /// Every provider of the effective configuration (empty when unset).
-pub fn all(config: &Config) -> &BTreeMap<String, ProviderDef> {
+/// `None` values are the YAML null-deletion markers and are skipped.
+pub fn all(config: &Config) -> &BTreeMap<String, Option<ProviderDef>> {
    config.settings.providers.as_ref().unwrap_or(&EMPTY)
 }

+/// The providers actually defined (null markers filtered out).
+pub fn defined(config: &Config) -> impl Iterator<Item = (&String, &ProviderDef)> {
+    all(config)
+        .iter()
+        .filter_map(|(k, v)| v.as_ref().map(|def| (k, def)))
+}
+
 /// Look up one provider by name.
 pub fn get<'a>(config: &'a Config, name: &str) -> Option<&'a ProviderDef> {
    config.settings.provider(name)
@@ -41,6 +49,38 @@ pub fn model_for<'a>(provider: &'a ProviderDef, explicit: Option<&'a str>) -> Op
        .or(provider.default_model.as_deref())
 }

+/// Sorted provider names (for error messages listing the registry).
+pub fn names(config: &Config) -> Vec<String> {
+    let mut v: Vec<String> = defined(config).map(|(k, _)| k.clone()).collect();
+    v.sort();
+    v
+}
+
+/// Resolve the provider + model of an agent at install time (issue #90):
+/// `flag --provider` > `agent.provider` > `settings.default_provider` ;
+/// `flag --model` > `agent.model` > `provider.default_model`.
+/// Returns None when no provider is configured at all.
+pub fn resolve_for<'a>(
+    config: &'a Config,
+    agent_provider: Option<&'a str>,
+    agent_model: Option<&'a str>,
+    flag_provider: Option<&'a str>,
+    flag_model: Option<&'a str>,
+) -> Option<(&'a str, &'a ProviderDef, Option<&'a str>)> {
+    let provider_name = flag_provider
+        .filter(|p| !p.is_empty())
+        .or(agent_provider.filter(|p| !p.is_empty()))
+        .or_else(|| default_name(config))?;
+    let def = get(config, provider_name)?;
+    let model = model_for(
+        def,
+        flag_model
+            .filter(|m| !m.is_empty())
+            .or(agent_model.filter(|m| !m.is_empty())),
+    );
+    Some((provider_name, def, model))
+}
+
 /// Provider names accept the same slug rule as agent names: [a-z0-9_-].
 pub fn is_valid_name(name: &str) -> bool {
    !name.is_empty()
@@ -60,19 +100,19 @@ mod tests {
        let mut providers = BTreeMap::new();
        providers.insert(
            "openai".to_string(),
-            ProviderDef {
+            Some(ProviderDef {
                base_url: "https://api.openai.com/v1".to_string(),
                default_model: Some("gpt-5.2".to_string()),
                models: vec!["gpt-5.2".to_string(), "gpt-5.1-mini".to_string()],
-            },
+            }),
        );
        providers.insert(
            "deepseek".to_string(),
-            ProviderDef {
+            Some(ProviderDef {
                base_url: "https://api.deepseek.com".to_string(),
                default_model: None,
                models: vec!["deepseek-chat".to_string()],
-            },
+            }),
        );
        c.settings.providers = Some(providers);
        c
@@ -114,4 +154,44 @@ mod tests {
        assert!(!is_valid_name(""));
        assert!(!is_valid_name("has space"));
    }
+
+    #[test]
+    fn resolve_for_flag_beats_agent_beats_default() {
+        let c = config_with();
+        // 1. Rien de précisé → default_provider (openai) + son default_model.
+        let (p, _, m) = resolve_for(&c, None, None, None, None).unwrap();
+        assert_eq!(p, "openai");
+        assert_eq!(m, Some("gpt-5.2"));
+        // 2. Le provider déclaré par l'agent gagne sur le défaut.
+        let (p, _, m) = resolve_for(&c, Some("deepseek"), None, None, None).unwrap();
+        assert_eq!(p, "deepseek");
+        assert_eq!(m, None, "deepseek n'a pas de default_model");
+        // 3. Le flag --provider gagne sur tout.
+        let (p, _, m) = resolve_for(&c, Some("openai"), None, Some("deepseek"), None).unwrap();
+        assert_eq!(p, "deepseek");
+        // 4. --model flag > agent.model > default_model.
+        let (_, _, m) = resolve_for(&c, None, Some("o4-mini"), None, None).unwrap();
+        assert_eq!(m, Some("o4-mini"));
+        let (_, _, m) = resolve_for(&c, None, Some("o4-mini"), None, Some("gpt-5.1-mini")).unwrap();
+        assert_eq!(m, Some("gpt-5.1-mini"));
+    }
+
+    #[test]
+    fn resolve_for_none_without_any_provider() {
+        let mut c = config_with();
+        c.settings.default_provider = None;
+        c.settings.providers = None;
+        assert!(resolve_for(&c, None, None, None, None).is_none());
+        // Un agent qui déclare son provider résout même sans défaut.
+        assert!(resolve_for(&c, Some("openai"), None, None, None).is_none());
+        let mut c2 = config_with();
+        c2.settings.default_provider = None;
+        assert_eq!(resolve_for(&c2, Some("openai"), None, None, None).unwrap().0, "openai");
+    }
+
+    #[test]
+    fn names_are_sorted() {
+        let c = config_with();
+        assert_eq!(names(&c), vec!["deepseek".to_string(), "openai".to_string()]);
+    }
 }
@@ -1753,6 +1753,9 @@ fn handle_line(
            agent: need("agent name")?,
            method: method_flag(),
            force: flag("--force"),
+            provider: opt_value("--provider"),
+            model: opt_value("--model"),
+            no_config: flag("--no-config"),
        },
        "uninstall" => Command::Uninstall {
            agent: need("agent name")?,
@@ -14,7 +14,7 @@ fn install_dry_run_creates_nothing() {
        &["install", "smelt", "--dry-run", "--yes"],
    );
    assert!(app.dry_run());
-    let code = install_cmd::run(&app, "smelt", None, false).unwrap();
+    let code = install_cmd::run(&app, "smelt", None, false, None, None, false).unwrap();
    assert_eq!(code, 0);
    // Nothing was written.
    assert!(!app.paths.install_dir.join("smelt").exists());