Feedsmith

Feedsmith

Use this skill for Feedsmith v3+ (feedsmith): parse and generate RSS, Atom, RDF, JSON Feed, and OPML with structure-preserving, typed APIs. Docs: v3.feedsmith.dev. Snapshot 3.0.0-rc.3 (2026-08-06).

Workflow

1. Inspect the local surface:
   • Installed feedsmith version and npm dist-tag (latest may still be 2.x — see source-map.md).
   • Parse vs generate vs OPML vs detect-only usage.
   • Dates: raw strings vs parseDateFn / Date on generate.
   • v2 leftovers: feedsmith/types, { lenient: true }, flat Atom strings, string RSS persons, singular dc.* fields.
2. Prefer dedicated parsers when format is known; use parseFeed only for unknown/mixed sources.
3. Refresh docs when tags drift. Start from source-map.md.
4. Route deeper detail:
   • Parse/detect/dates/errors: parsing.md
   • Generate, strict mode, stylesheets: generating.md
   • Formats, namespaces, types: formats-namespaces.md
   • v2→v3 breaking changes: migration-v2-to-v3.md
5. Prefer bun / bunx in command examples.

Core Judgment

• Preserve structure — do not invent a “universal flattened feed” layer; read format-specific fields and namespaces (feed.itunes, item.dc, …).
• Dates are strings by default on parse. Use parseDateFn to convert; errors from that fn are not swallowed.
• Generate is lenient by default in v3 (all fields optional). Use { strict: true } for compile-time spec-required fields + Date dates.
• Atom text/content are objects: title?.value, content?.value (not bare strings).
• RSS persons are objects: { email?, name?, link? } — not "a@b (Name)" strings.
• Types from main entry: RssFeed, AtomFeed, JsonFeed, RdfFeed, Opml, AnyFeed. No feedsmith/types.
• RDF generate is not available yet (parse yes). JSON Feed / RSS / Atom / OPML generate yes.
• Catch DetectError | MalformedError | ParseError | GenerateError — not only generic Error.
• Known format → dedicated parser (faster, more reliable than detect heuristics).

Verification

Prefer repository-owned commands. Cover the relevant subset:

• bun pm ls feedsmith / npm view feedsmith version dist-tags — confirm 3.x.
• Round-trip: parse fixture → assert key fields → generate → re-parse smoke.
• Typecheck Atom .value / RSS Person / dc.titles (plural) after upgrades.
• Strict generate: missing required fields should fail at compile time with { strict: true }.
• Error-path tests for bad XML / wrong format using dedicated error classes.

Report which checks ran, which did not, and version/tag assumptions that remain.