elicitation 0.9.1

Release Notes — elicitation 0.9.1

Release date: 2026-03-09

This is a patch release focused on architecture improvements, code quality, and
developer tooling. No public API removals. Several ergonomic additions make
elicit_* newtypes drop-in replacements for the types they wrap.

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Highlights

Single source of truth for workflows and emitted binaries

The biggest architectural win of this cycle. Previously, a workflow plugin
defined its tool parameters, its runtime dispatch logic, and its code-emission
logic in three separate places — keeping them in sync was manual and error-prone.

#[elicit_tool] now drives all three from one place:

#[elicit_tool]
#[derive(ElicitPlugin, serde::Deserialize)]
pub struct FetchAndExtractParams {
    pub url: UrlValid,
    pub selector: StringNonEmpty,
}

The macro reads the struct once and generates:

• MCP tool descriptor (name, schema)
• Runtime dispatch entry in the global inventory registry
• EmitCode impl that reproduces the binary calling this tool

The global emit registry (register_emit! + dispatch_emit) means any crate
that links a plugin automatically makes it available to code recovery — no manual
routing table needed.

CustomEmit<P> replaces emit = false

The old emit = false attribute silently dropped code emission. The new
CustomEmit<P> trait gives users an explicit escape hatch: implement
emit_code() yourself when the macro can't do it for you.

impl CustomEmit<MyParams> for MyParams {
    fn emit_code(&self) -> proc_macro2::TokenStream { ... }
}

If you can't auto-derive, you provide a function — the capability disappears
only if you choose not to implement it.

Cargo metadata replaces heuristic dep inference

EmitCode scaffolds need to declare which crates they depend on. The old
approach inferred deps by walking type name prefixes — fragile and often wrong.

The new all_crate_deps() reads Cargo.toml directly via the toml crate at
proc-macro expansion time ($CARGO_MANIFEST_DIR), resolves workspace = true
entries from the workspace root, and prepends the crate's own name/version
(which a crate never lists in its own [dependencies]). Result: the dep list
is always authoritative.

elicit_newtype_traits! — drop-in newtype compatibility

elicit_uuid::Uuid, elicit_url::Url, and friends wrap Arc<T> for
thread-safe shared ownership. But Arc<T> only derives Debug + Clone by
default, which blocked users from deriving PartialEq, Hash, Ord, etc. on
their own structs that contain these types.

The new elicit_newtype_traits! macro forwards standard traits from the inner
type to the wrapper:

// In elicit_uuid:
elicit_newtype_traits!(Uuid, uuid::Uuid, [cmp, display, from_str]);

Available flags: eq, eq_hash, ord, cmp (all 5 ordering traits),
display, from_str. This unblocks:

#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct MyRecord {
    pub id: elicit_uuid::Uuid,   // ✅ now works
    pub endpoint: elicit_url::Url,
}

Applied to: elicit_uuid::Uuid → [cmp, display, from_str],
elicit_url::Url → [cmp, display, from_str],
elicit_serde_json::JsonValue → [eq, display],
elicit_serde_json::JsonNumber → [eq, display].

Unified plugin migration

All workflow plugins across elicit_chrono, elicit_jiff, elicit_time,
elicit_url, and elicit_reqwest now use #[elicit_tool] +
#[derive(ElicitPlugin)]. This eliminates ~200 lines of hand-written
descriptor and dispatch boilerplate across the workspace and ensures every
plugin participates in the emit registry automatically.

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Developer tooling

just check-features — cargo-hack powerset (depth 2)

A new justfile recipe runs cargo hack --feature-powerset --depth 2 across
the workspace (122 feature combinations), tees output to a timestamped log,
and fails with a clear message if any warnings appear. This surfaced and fixed
six latent dead-code bugs caused by mismatched feature gates:

• use anodized::spec compiled when URL/regex types were absent
• kani_url_* / kani_uuid_* proof helpers visible when their type feature
  was off (even though proofs was on via the emit dep chain)
• Unused import clusters in datetime_specs.rs and http_specs.rs when
  datetime or reqwest features were absent
• dispatch_fetch_and_parse_emit was a public function in a private module
  with no export — now correctly re-exported under #[cfg(feature = "emit")]

The recipe lives in just pre-merge (not just ci or daily commits — the
122-combo run is a pre-PR gate, not a per-commit tax).

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What's next

The contract-carrying param types plan (CONTRACT_PARAMS_PLAN.md) is queued:
constrained types (UrlValid, F64Positive, etc.) propagating their contracts
into the MCP tool descriptor so agents see the validation rules without reading
source code.