> For the complete documentation index, see [llms.txt](https://docs.meridian.money/meridian-protocol-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.meridian.money/meridian-protocol-documentation/amm/pool-types/stable-pools.md). # Stable Pools Stable Pools are tailored for tokens pegged to specific values, synthetics like liquid-staking derivatives, or assets correlated with others. This category encompasses stablecoins, synthetic or wrapped assets, and staked derivatives (e.g., staked Aptos and Aptos). These pools facilitate low-impact, low-fee exchanges between assets converging on a relative value of "1". | Property | Weighted | | ------------------ | -------- | | Max Tokens in Pool | 2 | | Default Swap Fee | 0.05% | | Oracle Usage | None | **Stable Pool Math** To accommodate swaps between similar assets, Stable Pools utilize a distinct equation. Meridian employs a Stable Pool invariant (originally developed by Curve), which is as following: $$ A*n^n*\sum xᵢ+D=A*D*n^n+ \dfrac{D^{n+1}}{n^n\*\prod xᵢ} $$ **Amplification Factor** Stable pools can be fine-tuned using an "amplification factor" (A), which influences trade price impact. This factor determines how closely the pool's trading curve aligns with either the constant product or constant sum curve. A low amplification factor makes the pool's assets more susceptible to deviating from their peg, while a high factor requires significant trade volumes to shift relative asset values. It's worth noting that maximizing this factor isn't always optimal, as it can affect fee accumulation in the presence of alternative markets for similar assets. * **Low Amplification Factor**: In a pool with a low amplification factor, even small trades can cause noticeable deviations from the peg, making the pool less stable. Low A-factor is more suited for asset pairs that are less tightly correlated. * **High Amplification Factor**: A high amplification factor makes the pool more resistant to price deviations. For example, swapping between dollar-pegged stablecoins in a pool with a high amplification factor would result in minimal price impact, even for larger trade sizes. **Pool Parameters** The pool creator initially sets the amplification factor, which can only be modified subsequently through protocol governance. Any intended changes to this factor over time require the submission of a governance proposal. --- # 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 dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.meridian.money/meridian-protocol-documentation/amm/pool-types/stable-pools.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. 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.