# Extending the contextual glossary > 🇫🇷 [Version française](extending-glossary.md) The contextual glossary (Sprint 21) provides definitions, usage notes and primary references for the metrics shown in the report. A small `?` icon next to each metric column header opens a side panel with the entry's full content. ## Adding an entry The glossary lives in **two YAML files** that must stay in sync: - `picarones/report/glossary/fr.yaml` - `picarones/report/glossary/en.yaml` Each entry has the following schema: ```yaml your_metric_key: title: "Display name" definition: | Concise mathematical/operational definition of what this metric computes. measures: | What aspect of OCR/HTR quality this metric captures. usage: | When to look at this metric ; what threshold is meaningful. limits: | Known limitations, edge cases, sensitivity to corpus size, etc. reference: citation: "Author et al. (Year). Title. Journal, vol(num), pages." url: "https://doi.org/..." ``` ## Editorial rules - **One reference per metric** (primary citation), not a textbook excerpt. If multiple references are essential, use a top-level list and explain in `definition`. - **No recommendation** in `usage`. Describe when the metric is observable, not whether the user should trust it. - **Limits are mandatory** — every metric has limitations. Honesty about edge cases is what makes the glossary useful for scientific publication. ## Linking from the report The `?` icon is rendered automatically when a `