magi-code 0.77.1

Repository-aware CLI coding agent for terminal work
Documentation
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mod cache;
mod models_dev;
mod refresh;
pub(crate) mod types;

use crate::{
    config::{
        AuthState, CustomProviderConfig, McPaths, ProviderCredential, read_settings,
        set_selected_model,
    },
    providers::{self, AnthropicProvider, OpenAiCodexProvider, ReqwestHttpTransport},
};
use chrono::Utc;
use std::{sync::Arc, thread};

#[cfg(test)]
pub(crate) use cache::catalog_cache_path;
pub(crate) use cache::write_catalog_cache;
use cache::{
    metadata_entries_for_provider, read_catalog_cache, read_catalog_cache_for_configured_provider,
    read_custom_provider_catalog_cache, write_custom_provider_catalog_cache,
};
use models_dev::{
    ModelsDevLookup, SharedModelsDevLookup, effective_custom_provider_models_dev_namespace,
    enrich_custom_provider_catalog, enrich_custom_provider_catalog_with_models_dev_value,
    enrich_with_models_dev, enrich_with_models_dev_namespace, merge_custom_provider_extra_models,
    models_dev_source,
};
#[cfg(test)]
pub(crate) use refresh::CatalogRefreshFailureCategory;
pub(crate) use refresh::{
    CatalogRefreshOutcome, automatic_refresh_allowed, automatic_refresh_failed,
    automatic_refresh_suppressed, refresh_catalog_for_provider,
};
#[cfg_attr(
    not(test),
    expect(
        unused_imports,
        reason = "Retained as part of the model catalog type API."
    )
)]
pub use types::ModelCatalogServiceTier;
pub use types::{
    CachePreference, CatalogForUi, CatalogLoadResult, CatalogSource, ModelCatalogEntry, ModelId,
    ModelIdError,
};

const MAX_CUSTOM_PROVIDER_CATALOG_WORKERS: usize = 4;

#[cfg(test)]
pub(crate) use cache::write_catalog_cache_for_configured_provider;

#[cfg(test)]
#[path = "tests/mod.rs"]
mod tests;

pub fn validate_openai_codex_active(auth_state: &AuthState) -> Result<(), String> {
    let provider = auth_state.provider();
    if provider != providers::OPENAI_CODEX_PROVIDER {
        return Err(format!(
            "/setmodel requires active provider '{}'; current provider is '{provider}'",
            providers::OPENAI_CODEX_PROVIDER
        ));
    }
    Ok(())
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub struct AggregatedCatalogForUi {
    pub entries: Vec<ModelCatalogEntry>,
    pub notices: Vec<String>,
    pub stale: bool,
}

pub fn load_aggregated_catalog(
    paths: &McPaths,
    preference: CachePreference,
) -> AggregatedCatalogForUi {
    let mut models_dev = ModelsDevLookup::default();
    load_aggregated_catalog_with_models_dev(paths, preference, &mut models_dev)
}

fn load_aggregated_catalog_with_models_dev(
    paths: &McPaths,
    preference: CachePreference,
    models_dev: &mut ModelsDevLookup,
) -> AggregatedCatalogForUi {
    let mut entries = Vec::new();
    let mut notices = Vec::new();
    let mut stale = false;
    let settings = match read_settings(paths) {
        Ok(settings) => settings,
        Err(error) => {
            notices.push(format!(
                "settings.json could not be read; custom providers are unavailable until settings are fixed: {error}"
            ));
            Default::default()
        }
    };
    let auth = match crate::config::read_auth(paths) {
        Ok(auth) => auth,
        Err(error) => {
            notices.push(format!(
                "auth.json could not be read; openai-codex model discovery is unavailable until auth is fixed: {error}"
            ));
            Default::default()
        }
    };
    let credential = crate::config::resolve_provider_credential(
        providers::OPENAI_CODEX_PROVIDER,
        &auth,
        None,
        &settings.custom_providers,
    )
    .ok()
    .flatten();
    let openai_state =
        AuthState::for_provider(providers::OPENAI_CODEX_PROVIDER, credential.as_ref());
    let anthropic_credential = crate::config::resolve_provider_credential(
        providers::ANTHROPIC_PROVIDER,
        &auth,
        None,
        &settings.custom_providers,
    )
    .ok()
    .flatten();
    let anthropic_state =
        AuthState::for_provider(providers::ANTHROPIC_PROVIDER, anthropic_credential.as_ref());
    let shared_models_dev = Arc::new(SharedModelsDevLookup::from_seeded(models_dev));
    let mut custom_jobs = Vec::new();
    for (provider, custom) in settings.custom_providers {
        if let Err(error) = crate::config::normalize_custom_provider_base_url(&custom.base_url) {
            notices.push(format!(
                "custom provider '{provider}' has invalid base_url and was skipped: {error}"
            ));
            continue;
        }
        let credential = match &custom.api_key_env_var {
            Some(env_var) => match std::env::var(env_var).ok().filter(|v| !v.is_empty()) {
                Some(key) => Some(ProviderCredential::ApiKey { key }),
                None => {
                    notices.push(format!(
                        "custom provider '{provider}' configured but not ready; set {env_var}"
                    ));
                    None
                }
            },
            None => Some(ProviderCredential::NoAuth),
        };
        let Some(credential) = credential else {
            continue;
        };
        custom_jobs.push((provider, custom, credential));
    }

    let provider_results = thread::scope(|scope| {
        let mut base_handles = Vec::new();
        {
            let paths = paths.clone();
            let shared_models_dev = Arc::clone(&shared_models_dev);
            base_handles.push(scope.spawn(move || {
                load_openai_codex_catalog_with_models_dev(
                    &paths,
                    &openai_state,
                    preference,
                    Some(&*shared_models_dev),
                )
            }));
        }
        {
            let paths = paths.clone();
            base_handles.push(
                scope.spawn(move || load_anthropic_catalog(&paths, &anthropic_state, preference)),
            );
        }

        let mut custom_results = Vec::new();
        for chunk in custom_jobs.chunks(MAX_CUSTOM_PROVIDER_CATALOG_WORKERS) {
            let handles = chunk
                .iter()
                .map(|(provider, custom, credential)| {
                    let paths = paths.clone();
                    let shared_models_dev = Arc::clone(&shared_models_dev);
                    scope.spawn(move || {
                        load_custom_provider_catalog_with_models_dev(
                            &paths,
                            provider,
                            custom,
                            Some(credential),
                            preference,
                            Some(&*shared_models_dev),
                        )
                    })
                })
                .collect::<Vec<_>>();
            custom_results.extend(handles.into_iter().map(|handle| match handle.join() {
                Ok(result) => result,
                Err(_) => Err("model catalog worker panicked".to_string()),
            }));
        }
        let mut results = base_handles
            .into_iter()
            .map(|handle| match handle.join() {
                Ok(result) => result,
                Err(_) => Err("model catalog worker panicked".to_string()),
            })
            .collect::<Vec<_>>();
        results.extend(custom_results);
        results
    });

    for result in provider_results {
        match result {
            Ok(result) => {
                entries.extend(result.entries);
                match result.source {
                    CatalogSource::StaleCache { diagnostic } => {
                        stale = true;
                        notices.push(diagnostic);
                    }
                    source => {
                        if let Some(notice) = source.notice() {
                            notices.push(notice);
                        }
                    }
                }
            }
            Err(error) => notices.push(error),
        }
    }
    AggregatedCatalogForUi {
        entries,
        notices,
        stale,
    }
}

fn custom_provider_catalog_api_key(
    provider: &str,
    credential: Option<&ProviderCredential>,
) -> Result<Option<String>, String> {
    match credential {
        Some(ProviderCredential::ApiKey { key }) => Ok(Some(key.clone())),
        Some(ProviderCredential::NoAuth) => Ok(None),
        Some(_) => Err(format!(
            "provider '{provider}' requires custom-provider auth mode, not OAuth token"
        )),
        None => Err(format!(
            "custom provider '{provider}' is configured but not ready"
        )),
    }
}

fn load_custom_provider_catalog(
    paths: &McPaths,
    provider: &str,
    custom: &CustomProviderConfig,
    credential: Option<&ProviderCredential>,
    preference: CachePreference,
) -> Result<CatalogLoadResult, String> {
    load_custom_provider_catalog_with_models_dev(
        paths, provider, custom, credential, preference, None,
    )
}

fn load_custom_provider_catalog_with_models_dev(
    paths: &McPaths,
    provider: &str,
    custom: &CustomProviderConfig,
    credential: Option<&ProviderCredential>,
    preference: CachePreference,
    models_dev: Option<&SharedModelsDevLookup>,
) -> Result<CatalogLoadResult, String> {
    crate::config::normalize_custom_provider_base_url(&custom.base_url)
        .map_err(|error| format!("custom provider '{provider}' has invalid base_url: {error}"))?;
    let extra_models =
        crate::config::normalized_extra_models(&custom.extra_models).map_err(|error| {
            format!("custom provider '{provider}' has invalid extra_models: {error}")
        })?;
    let api_key = custom_provider_catalog_api_key(provider, credential)?;
    if let Some(cached) = read_custom_provider_catalog_cache(paths, provider, custom)
        && cached.expires_at > Utc::now()
    {
        return Ok(CatalogLoadResult {
            entries: cached.entries,
            source: CatalogSource::FreshCache,
        });
    }
    let live = crate::providers::OpenAiCompatibleProvider::custom(
        provider.to_string(),
        providers::DEFAULT_CODEX_MODEL,
        api_key,
        custom.base_url.clone(),
        custom.use_responses_endpoint,
        crate::providers::ReqwestHttpTransport,
    )
    .discover_model_catalog()
    .and_then(|items| match models_dev {
        Some(lookup) => lookup
            .get()
            .map(|value| {
                enrich_custom_provider_catalog_with_models_dev_value(items, provider, custom, value)
            })
            .map_err(|error| anyhow::anyhow!("models.dev enrichment fetch failed: {error}")),
        None => enrich_custom_provider_catalog(items, provider, custom),
    })
    .and_then(|items| {
        merge_custom_provider_extra_models(items, provider, &extra_models)
            .map_err(anyhow::Error::msg)
    })
    .and_then(|items| {
        write_custom_provider_catalog_cache(paths, provider, custom, &items)?;
        Ok(items)
    });
    match live {
        Ok(entries) => {
            let namespace = effective_custom_provider_models_dev_namespace(provider, custom);
            Ok(CatalogLoadResult {
                source: models_dev_source(&entries, models_dev, namespace),
                entries,
            })
        }

        Err(error) => {
            if preference == CachePreference::AllowStale
                && let Some(cached) = read_custom_provider_catalog_cache(paths, provider, custom)
            {
                return Ok(CatalogLoadResult {
                    entries: cached.entries,
                    source: CatalogSource::StaleCache {
                        diagnostic: format!(
                            "using stale {provider} model catalog; live refresh failed: {error}"
                        ),
                    },
                });
            }
            Err(format!("{provider} model discovery unavailable: {error}"))
        }
    }
}

pub fn load_openai_codex_catalog(
    paths: &McPaths,
    auth_state: &AuthState,
    preference: CachePreference,
) -> Result<CatalogLoadResult, String> {
    load_openai_codex_catalog_with_models_dev(paths, auth_state, preference, None)
}

fn load_openai_codex_catalog_with_models_dev(
    paths: &McPaths,
    auth_state: &AuthState,
    preference: CachePreference,
    models_dev: Option<&SharedModelsDevLookup>,
) -> Result<CatalogLoadResult, String> {
    validate_openai_codex_active(auth_state)?;
    if let Some(cached) = read_catalog_cache(paths, providers::OPENAI_CODEX_PROVIDER)
        && cached.expires_at > Utc::now()
    {
        return Ok(CatalogLoadResult {
            entries: cached.entries,
            source: CatalogSource::FreshCache,
        });
    }

    let live_result = crate::config::refreshed_codex_auth_state(paths, auth_state)
        .map_err(|error| format!("credential refresh failed: {error}"))
        .and_then(|refreshed_auth_state| {
            fetch_live_openai_codex_catalog_with_models_dev(&refreshed_auth_state, models_dev)
        })
        .and_then(|entries| {
            write_catalog_cache(paths, providers::OPENAI_CODEX_PROVIDER, &entries).map_err(
                |error| format!("openai-codex model catalog cache write failed: {error}"),
            )?;
            Ok(entries)
        });

    match live_result {
        Ok(entries) => Ok(CatalogLoadResult {
            source: models_dev_source(&entries, models_dev, "openai"),
            entries,
        }),
        Err(error) => {
            if preference == CachePreference::AllowStale
                && let Some(cached) = read_catalog_cache(paths, providers::OPENAI_CODEX_PROVIDER)
                && !cached.entries.is_empty()
            {
                return Ok(CatalogLoadResult {
                    entries: cached.entries,
                    source: CatalogSource::StaleCache {
                        diagnostic: format!(
                            "using stale openai-codex model catalog; live refresh failed: {error}"
                        ),
                    },
                });
            }
            Err(format!(
                "openai-codex model discovery unavailable: {error}; run /login openai-codex and retry /setmodel when network access is available"
            ))
        }
    }
}

fn fetch_live_openai_codex_catalog_with_models_dev(
    auth_state: &AuthState,
    models_dev: Option<&SharedModelsDevLookup>,
) -> Result<Vec<ModelCatalogEntry>, String> {
    let AuthState::Ready {
        provider,
        credential,
    } = auth_state
    else {
        return Err("provider auth is not configured".to_string());
    };
    if provider != providers::OPENAI_CODEX_PROVIDER {
        return Err(format!(
            "provider '{provider}' does not support dynamic model discovery"
        ));
    }
    let ProviderCredential::OAuth { access, account_id } = credential else {
        return Err(
            "openai-codex model discovery requires provider-keyed OAuth auth, not an API key"
                .to_string(),
        );
    };
    let provider = OpenAiCodexProvider::new(
        providers::DEFAULT_CODEX_MODEL,
        access.clone(),
        account_id.clone(),
        ReqwestHttpTransport,
    );
    provider
        .discover_model_catalog()
        .map_err(|error| error.to_string())
        .and_then(|entries| match models_dev {
            Some(lookup) => lookup
                .get()
                .map(|value| enrich_with_models_dev_namespace(entries, value, "openai"))
                .map_err(|error| format!("models.dev enrichment fetch failed: {error}")),
            None => enrich_with_models_dev(entries)
                .map_err(|error| format!("models.dev enrichment fetch failed: {error}")),
        })
}

fn fetch_live_anthropic_catalog(auth_state: &AuthState) -> Result<Vec<ModelCatalogEntry>, String> {
    let AuthState::Ready {
        provider,
        credential,
    } = auth_state
    else {
        return Err("provider auth is not configured".to_string());
    };
    if provider != providers::ANTHROPIC_PROVIDER {
        return Err(format!(
            "provider '{provider}' does not support Anthropic model discovery"
        ));
    }
    let ProviderCredential::ApiKey { key } = credential else {
        return Err(
            "anthropic model discovery requires API-key auth, not OAuth or no-auth".to_string(),
        );
    };
    AnthropicProvider::new(
        providers::DEFAULT_ANTHROPIC_MODEL,
        key.clone(),
        ReqwestHttpTransport,
    )
    .discover_model_catalog()
    .map_err(|error| error.to_string())
}
pub fn load_anthropic_catalog(
    paths: &McPaths,
    auth_state: &AuthState,
    preference: CachePreference,
) -> Result<CatalogLoadResult, String> {
    if let Some(cached) = read_catalog_cache(paths, providers::ANTHROPIC_PROVIDER)
        && cached.expires_at > Utc::now()
    {
        return Ok(CatalogLoadResult {
            entries: cached.entries,
            source: CatalogSource::FreshCache,
        });
    }
    let live_result = fetch_live_anthropic_catalog(auth_state).and_then(|entries| {
        write_catalog_cache(paths, providers::ANTHROPIC_PROVIDER, &entries)
            .map_err(|error| format!("anthropic model catalog cache write failed: {error}"))?;
        Ok(entries)
    });
    match live_result {
        Ok(entries) => Ok(CatalogLoadResult {
            entries,
            source: CatalogSource::Live,
        }),
        Err(error) => {
            if preference == CachePreference::AllowStale
                && let Some(cached) = read_catalog_cache(paths, providers::ANTHROPIC_PROVIDER)
                && !cached.entries.is_empty()
            {
                return Ok(CatalogLoadResult {
                    entries: cached.entries,
                    source: CatalogSource::StaleCache {
                        diagnostic: format!(
                            "using stale anthropic model catalog; live refresh failed: {error}"
                        ),
                    },
                });
            }
            Err(format!(
                "anthropic model discovery unavailable: {error}; set ANTHROPIC_API_KEY and retry /setmodel when network access is available"
            ))
        }
    }
}

/// Read only the fingerprint-validated cache; never perform discovery or refresh credentials.
pub(crate) fn cached_catalog_for_service(paths: &McPaths, provider: &str) -> Option<CatalogForUi> {
    let cache = read_catalog_cache_for_configured_provider(paths, provider)?;
    Some(CatalogForUi {
        entries: cache.entries,
        stale: cache.expires_at <= Utc::now(),
        notice: None,
    })
}

pub(crate) fn cached_model_thinking_metadata(
    paths: &McPaths,
    provider: &str,
    model: &str,
) -> Option<crate::thinking::CatalogThinkingMetadata> {
    let cache = read_catalog_cache_for_configured_provider(paths, provider)?;
    if cache.expires_at <= Utc::now() {
        return None;
    }
    cache
        .entries
        .iter()
        .find(|entry| entry.provider == provider && entry.model == model)
        .map(|entry| crate::thinking::CatalogThinkingMetadata {
            reasoning_efforts: entry.reasoning_efforts.clone(),
            supports_reasoning: entry
                .supports_reasoning
                .or(entry.legacy_supports_reasoning_effort),
        })
}

pub fn persist_selected_model(paths: &McPaths, provider: &str, model: &str) -> anyhow::Result<()> {
    set_selected_model(paths, provider, model)
}

pub(crate) fn resolve_codex_fast_service_tier(
    provider: &str,
    model: &str,
    entry: &ModelCatalogEntry,
) -> Option<String> {
    if provider != providers::OPENAI_CODEX_PROVIDER
        || entry.provider != providers::OPENAI_CODEX_PROVIDER
    {
        return None;
    }
    if let Some(service_tiers) = &entry.service_tiers {
        return service_tiers.iter().find_map(|tier| {
            (tier.name.trim().eq_ignore_ascii_case("fast") && !tier.id.trim().is_empty())
                .then(|| tier.id.clone())
        });
    }
    codex_model_supports_fast(model).then(|| "fast".to_string())
}

pub(crate) fn resolve_codex_fast_service_tier_from_entries(
    provider: &str,
    model: &str,
    entries: Option<&[ModelCatalogEntry]>,
) -> Option<String> {
    if provider != providers::OPENAI_CODEX_PROVIDER {
        return None;
    }
    let Some(entries) = entries else {
        return codex_model_supports_fast(model).then(|| "fast".to_string());
    };
    let normalized = providers::normalize_codex_model(model);
    let Some(entry) = entries.iter().find(|entry| {
        entry.provider == providers::OPENAI_CODEX_PROVIDER
            && (entry.model == model
                || entry.model == normalized
                || providers::normalize_codex_model(&entry.model) == normalized)
    }) else {
        return codex_model_supports_fast(model).then(|| "fast".to_string());
    };
    resolve_codex_fast_service_tier(provider, model, entry)
}

pub(crate) fn resolve_codex_fast_service_tier_from_catalog_entries(
    provider: &str,
    model: &str,
    entries: &[ModelCatalogEntry],
) -> Option<String> {
    resolve_codex_fast_service_tier_from_entries(provider, model, Some(entries))
}

pub(crate) fn cached_codex_fast_service_tier(paths: &McPaths, model: &str) -> Option<String> {
    let cached = metadata_entries_for_provider(paths, providers::OPENAI_CODEX_PROVIDER);
    resolve_codex_fast_service_tier_from_entries(
        providers::OPENAI_CODEX_PROVIDER,
        model,
        cached.as_deref(),
    )
}

fn codex_model_supports_fast(model: &str) -> bool {
    let model = providers::normalize_codex_model(model);
    let Some((major, minor_and_variant)) = model
        .strip_prefix("gpt-")
        .and_then(|model| model.split_once('.'))
    else {
        return false;
    };
    let Some(major) = (!major.is_empty())
        .then(|| major.parse::<u64>().ok())
        .flatten()
    else {
        return false;
    };
    let minor_end = minor_and_variant
        .find(|character: char| !character.is_ascii_digit())
        .unwrap_or(minor_and_variant.len());
    let minor_text = &minor_and_variant[..minor_end];
    let Some(minor) = (!minor_text.is_empty())
        .then(|| minor_text.parse::<u64>().ok())
        .flatten()
    else {
        return false;
    };
    let variant = &minor_and_variant[minor_end..];
    if !variant.is_empty() && !matches!(variant.as_bytes().first(), Some(b'.' | b'-' | b'_')) {
        return false;
    }
    major > 5 || (major == 5 && minor >= 4)
}

pub fn cached_model_context_window(paths: &McPaths, provider: &str, model: &str) -> Option<usize> {
    let cached = metadata_entries_for_provider(paths, provider)?;
    let context_window = cached
        .iter()
        .find(|entry| entry.provider == provider && entry.model == model)
        .and_then(|entry| entry.context_window)?;
    usize::try_from(context_window).ok()
}

pub fn cached_model_max_output_tokens(paths: &McPaths, provider: &str, model: &str) -> Option<u64> {
    let cached = metadata_entries_for_provider(paths, provider)?;
    cached
        .iter()
        .find(|entry| entry.provider == provider && entry.model == model)
        .and_then(|entry| entry.max_output_tokens)
}

fn normalize_switch_model_id(model_id: ModelId) -> Result<ModelId, ModelIdError> {
    if model_id.provider() == providers::OPENAI_CODEX_PROVIDER {
        let normalized = providers::normalize_codex_model(model_id.model());
        if normalized != model_id.model() {
            return ModelId::from_parts(model_id.provider(), normalized);
        }
    }
    Ok(model_id)
}

pub fn switch_model(
    paths: &McPaths,
    auth_state: &AuthState,
    model_id: &str,
) -> anyhow::Result<(String, String, Option<String>)> {
    let (model_id, catalog) = switch_model_internal(paths, auth_state, model_id)?;
    let notice = catalog.source.notice();
    persist_selected_model(paths, model_id.provider(), model_id.model())?;
    Ok((
        model_id.provider().to_string(),
        model_id.model().to_string(),
        notice,
    ))
}

pub(crate) fn resolve_model_with_fast_service_tier(
    paths: &McPaths,
    auth_state: &AuthState,
    model_id: &str,
) -> anyhow::Result<(String, String, Option<String>, Option<String>)> {
    let (model_id, catalog) = switch_model_internal(paths, auth_state, model_id)?;
    let service_tier = resolve_codex_fast_service_tier_from_catalog_entries(
        model_id.provider(),
        model_id.model(),
        &catalog.entries,
    );
    Ok((
        model_id.provider().to_string(),
        model_id.model().to_string(),
        catalog.source.notice(),
        service_tier,
    ))
}

fn switch_model_internal(
    paths: &McPaths,
    _auth_state: &AuthState,
    model_id: &str,
) -> anyhow::Result<(ModelId, CatalogLoadResult)> {
    let model_id = normalize_switch_model_id(ModelId::parse(model_id)?)?;
    crate::config::reject_retired_provider_selection(model_id.provider(), model_id.model())?;
    let normalized_model_id = model_id.to_string();
    let settings = read_settings(paths)?;
    if crate::config::disabled_model_ids_from_settings(&settings).contains(&normalized_model_id) {
        anyhow::bail!("cannot select disabled model: {normalized_model_id}");
    }
    let catalog = {
        let auth = crate::config::read_auth(paths)?;
        let target_credential = crate::config::resolve_provider_credential(
            model_id.provider(),
            &auth,
            None,
            &settings.custom_providers,
        )?;
        if let Some(custom) = settings.custom_providers.get(model_id.provider())
            && target_credential.is_none()
        {
            let Some(env_var) = &custom.api_key_env_var else {
                anyhow::bail!(
                    "custom provider '{}' is configured for no-auth but is not ready",
                    model_id.provider()
                );
            };
            anyhow::bail!(
                "custom provider '{}' is configured but not ready; set {env_var} before selecting models",
                model_id.provider()
            );
        }
        let target_auth_state = AuthState::for_provider_with_custom(
            model_id.provider(),
            target_credential.as_ref(),
            &settings.custom_providers,
        );
        if model_id.provider() == providers::OPENAI_CODEX_PROVIDER {
            load_openai_codex_catalog(paths, &target_auth_state, CachePreference::AllowStale)
                .map_err(|e| anyhow::anyhow!(e))?
        } else if model_id.provider() == providers::ANTHROPIC_PROVIDER {
            load_anthropic_catalog(paths, &target_auth_state, CachePreference::AllowStale)
                .map_err(|e| anyhow::anyhow!(e))?
        } else if let Some(custom) = settings.custom_providers.get(model_id.provider()) {
            load_custom_provider_catalog(
                paths,
                model_id.provider(),
                custom,
                target_credential.as_ref(),
                CachePreference::AllowStale,
            )
            .map_err(|e| anyhow::anyhow!(e))?
        } else {
            anyhow::bail!(
                "unsupported provider '{}'; configure it with /login custom-provider before selecting models",
                model_id.provider()
            );
        }
    };
    if !catalog
        .entries
        .iter()
        .any(|entry| entry.provider == model_id.provider() && entry.model == model_id.model())
    {
        anyhow::bail!("model '{model_id}' is not available in the discovered provider catalog");
    }
    Ok((model_id, catalog))
}

pub fn model_usage() -> &'static str {
    "usage: /setmodel <provider>/<model-name> (examples: /setmodel openai-codex/<model-name>, /setmodel anthropic/<model-name>, /setmodel custom-local/<model-name>)"
}