> For the complete documentation index, see [llms.txt](https://docs.os.uk/osngd/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/osngd/using-os-ngd-data/os-ngd-transport/street-lights/known-limitations.md). # Known limitations There are two known limitations for Street Light data: * **Street Light Completeness:** Street Lights have been captured from aerial imagery and therefore there are some limitations to completeness. Where features are not visible from aerial imagery (for example, where they are obscured by tree cover or not visible due to urban shading), these will not be included. * **Overlighting and Underlighting:** Street Light coverage attribution on Road Links and Path Links is indicative only, and there may be some instances of overlighting and underlighting. An algorithm is used to give an indication of how well-lit a link is; this algorithm is based on an inferred light radius and does not account for information such as the height of a lamp post, the type of bulb, or the presence of any light-blocking obstructions or buildings. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://docs.os.uk/osngd/using-os-ngd-data/os-ngd-transport/street-lights/known-limitations.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.