---
title: "Standard library | Grafana Agent documentation"
description: "The standard library is a list of functions used in expressions when assigning values to attributes"
---

> For a curated documentation index, see [llms.txt](/llms.txt). For the complete documentation index, see [llms-full.txt](/llms-full.txt).

# Standard library

The standard library is a list of functions which can be used in expressions when assigning values to attributes.

All standard library functions are [pure functions](https://en.wikipedia.org/wiki/Pure_function): they will always return the same output if given the same input.

- [coalesce](https://grafana.com/docs/agent/latest/flow/reference/stdlib/coalesce/)
- [concat](https://grafana.com/docs/agent/latest/flow/reference/stdlib/concat/)
- [constants](https://grafana.com/docs/agent/latest/flow/reference/stdlib/constants/)
- [env](https://grafana.com/docs/agent/latest/flow/reference/stdlib/env/)
- [format](https://grafana.com/docs/agent/latest/flow/reference/stdlib/format/)
- [join](https://grafana.com/docs/agent/latest/flow/reference/stdlib/join/)
- [json\_decode](https://grafana.com/docs/agent/latest/flow/reference/stdlib/json_decode/)
- [json\_path](https://grafana.com/docs/agent/latest/flow/reference/stdlib/json_path/)
- [nonsensitive](https://grafana.com/docs/agent/latest/flow/reference/stdlib/nonsensitive/)
- [replace](https://grafana.com/docs/agent/latest/flow/reference/stdlib/replace/)
- [split](https://grafana.com/docs/agent/latest/flow/reference/stdlib/split/)
- [to\_lower](https://grafana.com/docs/agent/latest/flow/reference/stdlib/to_lower/)
- [to\_upper](https://grafana.com/docs/agent/latest/flow/reference/stdlib/to_upper/)
- [trim](https://grafana.com/docs/agent/latest/flow/reference/stdlib/trim/)
- [trim\_prefix](https://grafana.com/docs/agent/latest/flow/reference/stdlib/trim_prefix/)
- [trim\_space](https://grafana.com/docs/agent/latest/flow/reference/stdlib/trim_space/)
- [trim\_suffix](https://grafana.com/docs/agent/latest/flow/reference/stdlib/trim_suffix/)