What causes "Warning: no characters file!" in stanfordnlp/CoreNLP?

Set properties.setProperty("charactersPath", "/path/to/characters.tsv") before annotating

Warning: no characters file!

Error message

Warning: no characters file!

What it means

The QuoteAttributionAnnotator needs a characters file (property 'charactersPath') listing book characters for mention matching. If it is not set and verbose=true, this warning is logged; the annotator proceeds without character metadata, degrading mention/character results.

Solutions

Set properties.setProperty("charactersPath", "/path/to/characters.tsv") before annotating
Run the character/mention extraction step to generate the characters file
Check the file exists and is readable at the given path
Enable verbose=true to see all missing booknlp inputs at once

Example fix

// before
props.setProperty("quote.attribution.sieves", DEFAULT_QMSIEVES); // no charactersPath
// after
props.setProperty("charactersPath", "/data/book/characters.tsv");

Defensive patterns

Strategy: validation

Validate before calling

String chars = props.getProperty("charactersPath");
if (chars == null || !new File(chars).canRead()) {
    throw new IllegalArgumentException("'charactersPath' must point to a readable characters file");
}

Prevention

Verify charactersPath file exists and is readable before constructing the annotator
Generate the characters/mentions file as part of your preprocessing pipeline

When it happens

Trigger: Including 'quoteattribution' in annotators without setting 'charactersPath'; the public constructor QuoteAttributionAnnotator(Properties) detects null CHARACTERS_FILE while VERBOSE is enabled.

Common situations: Forgetting the characters/mentions TSV produced by the booknlp preprocessing step; pointing charactersPath at a nonexistent path in another property and leaving this one unset; sample configs from tutorials only partially copied.

Understand the failure class

Background: "missing required config value" errors: why libraries refuse to start when a configuration key is empty, unset, or blank — this error's family across 48 libraries.

Related errors

AI-assisted analysis of stanfordnlp/CoreNLP@1b7edd19c4 (2026-09-10). Data as JSON: /api/errors/f725e3b477691ae4. Report an issue: GitHub.

Appendix: source

Thrown at src/edu/stanford/nlp/pipeline/QuoteAttributionAnnotator.java:167

  private final Map<String, Person.Gender> genderMap;
  private Map<String, List<Person>> characterMap;
  private final String qmSieveList;
  private final String msSieveList;
  private final DependencyParser parser;

  public QuoteAttributionAnnotator(Properties props) {

    VERBOSE = PropertiesUtils.getBool(props, "verbose", false);

    Timing timer = null;
    COREF_PATH = props.getProperty("booknlpCoref", null);
    if (COREF_PATH == null && VERBOSE) {
      log.err("Warning: no coreference map!");
    }
    MODEL_PATH = props.getProperty("modelPath", DEFAULT_MODEL_PATH);
    CHARACTERS_FILE = props.getProperty("charactersPath", null);
    if(CHARACTERS_FILE == null && VERBOSE) {
      log.err("Warning: no characters file!");
    }
    qmSieveList = props.getProperty("QMSieves", DEFAULT_QMSIEVES);
    msSieveList = props.getProperty("MSSieves", DEFAULT_MSSIEVES);

    if (VERBOSE) {
      timer = new Timing();
      log.info("Loading QuoteAttribution coref [" + COREF_PATH + "]...");
      log.info("Loading QuoteAttribution characters [" + CHARACTERS_FILE + "]...");
    }
    // loading all our word lists
    FAMILY_WORD_LIST = props.getProperty("familyWordsFile", FAMILY_WORD_LIST);
    ANIMACY_WORD_LIST = props.getProperty("animacyWordsFile", ANIMACY_WORD_LIST);
    GENDER_WORD_LIST = props.getProperty("genderNamesFile", GENDER_WORD_LIST);
    familyRelations = QuoteAttributionUtils.readFamilyRelations(FAMILY_WORD_LIST);
    genderMap = QuoteAttributionUtils.readGenderedNounList(GENDER_WORD_LIST);
    animacyList = QuoteAttributionUtils.readAnimacyList(ANIMACY_WORD_LIST);
    if (characterMap != null) { // todo [cdm 2020]: Shouldn't this be testing against CHARACTERS_FILE?
      characterMap = QuoteAttributionUtils.readPersonMap(CHARACTERS_FILE);

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