Before connecting any feed to an automation tool, it’s worth confirming the feed itself is actually valid. A malformed RSS feed doesn’t always fail loudly — sometimes it just silently drops items, misreads dates, or shows garbled titles in whatever tool is reading it, and the feed’s own publisher may never notice because they’re not the one consuming it.
RSS 2.0 is a formal XML specification, which means a feed can be checked against a defined set of rules the same way any XML document can be validated against a schema. Validity issues range from small (a missing required element, an improperly escaped character) to serious (broken XML structure that stops a feed reader from parsing the file at all). Most modern CMS platforms generate valid feeds by default, but custom feed generators, older plugins, or manually edited feed templates are where problems tend to creep in.
pubDate in the wrong format can cause automation tools to sort items incorrectly, or in some cases skip them.title or link at the channel level; their absence can cause stricter parsers to reject the feed outright.A human skimming a feed reader might not notice a slightly malformed date or an oddly encoded character — the reader software often quietly works around minor issues. Automation tools that trigger real actions (like posting to social media) are less forgiving: a parsing hiccup can mean a post silently never happens, happens with garbled text, or in rare cases gets flagged as a duplicate when it isn’t. If your automated posts are behaving unpredictably and you’ve ruled out the more common causes (like an excerpt-only feed or a caching delay), running your feed through a validator is a fast way to rule out or confirm a structural problem.
Validators typically separate findings into errors (specification violations that can break parsing) and warnings (deviations from best practice that most parsers will still handle gracefully). A feed with only warnings is usually safe to use; a feed with errors is worth fixing at the source, since different automation tools and feed readers handle the same error differently — what one tool tolerates, another might reject.
If you’re automating a feed you don’t control (a partner site, a client’s separate CMS) and it has validation errors, a feed-proxy or feed-repair service can sometimes clean up common issues before the feed reaches your automation tool, though this adds a dependency and a potential point of failure of its own. For feeds you do control, fixing the actual generation source (CMS settings, a plugin, or custom feed template code) is the more durable solution.
PostRSS, like most modern feed-reading tools, is generally tolerant of minor validation warnings and can successfully read feeds with small deviations from the spec — but feeds with serious structural errors (broken XML, missing required elements) can cause items to be missed or misread regardless of which tool is reading them.
Once your feed is confirmed valid and your CMS/plugin setup hasn’t changed, ongoing re-validation usually isn’t necessary — it’s most useful to check after a CMS update, plugin change, or theme switch, any of which can alter how your feed is generated.
Yes — validity only confirms the XML structure is well-formed and spec-compliant, not that the content inside is what you want automated. A perfectly valid feed can still lack a proper featured image or have a title that’s awkward when posted verbatim, which validation tools don’t check for.
Feed validation is a five-minute check that rules out an entire category of automation problems before they happen. Running a new or unfamiliar feed through the W3C Feed Validation Service or RSS Board Validator before connecting it to any automation tool, PostRSS included, is a cheap insurance policy against silent, hard-to-diagnose posting failures down the line.