convex-cursorrules-prompt-file

convex-cursorrules-prompt-file is a cursor rule for coding agents from PatrickJS/awesome-cursorrules. It costs 6,270 tokens per session, scanned A, original, CC0-1.0.

A set of coding guidelines for Convex, a backend platform for building applications. It covers how to write database functions, web endpoints, and input validators.

In plain words
What is it for?
It is for writing Convex queries, updates, web endpoints, and validation rules in a TypeScript project.
Why use it?
It helps keep Convex code consistent with the platform’s current syntax and practices.

Cursor rule

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/patrickjs/awesome-cursorrules/convex-cursorrules-prompt-file
Clone the repo
git clone --depth 1 https://github.com/PatrickJS/awesome-cursorrules

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for convex-cursorrules-prompt-file

README.md
[![agentmods](https://agentmods.dev/badge/rules/patrickjs/awesome-cursorrules/convex-cursorrules-prompt-file.svg)](https://agentmods.dev/rules/patrickjs/awesome-cursorrules/convex-cursorrules-prompt-file)
Your own site
<a href="https://agentmods.dev/rules/patrickjs/awesome-cursorrules/convex-cursorrules-prompt-file"><img src="https://agentmods.dev/badge/rules/patrickjs/awesome-cursorrules/convex-cursorrules-prompt-file.svg" alt="Measured on agentmods" height="20"></a>
Per session 6,270 This file is loaded in full into every session.
When invoked 6,270 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.06270 $0.06270
Opus 5 $0.03135 $0.03135
Sonnet 5 $0.01254 $0.01254
Haiku 4.5 $0.00627 $0.00627

Measured 4d ago against content hash 2cbb87de5845, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

convex-cursorrules-prompt-file scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

6 near-identical copies found in the catalogue:

rules/convex-cursorrules-prompt-file.mdc · 676 lines

How it starts

The opening of the file, as written. The whole thing — 676 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Convex guidelines

Function guidelines

New function syntax

  • ALWAYS use the new function syntax for Convex functions. For example: typescript import { query } from "./_generated/server"; import { v } from "convex/values"; export const f = query({ args: {}, returns: v.null(), handler: async (ctx, args) => { // Function body }, });

Http endpoint syntax

  • HTTP endpoints are defined in convex/http.ts and require an httpAction decorator. For example: typescript import { httpRouter } from "convex/server"; import { httpAction } from "./_generated/server"; const http = httpRouter(); http.route({ path: "/echo", method: "POST", handler: httpAction(async (ctx, req) => { const body = await req.bytes(); return new Response(body, { status: 200 }); }), });
  • HTTP endpoints are always registered at the exact path you specify in the path field. For example, if you specify /api/someRoute, the endpoint will be registered at /api/someRoute.

Validators

  • Below is an example of an array validator: ```typescript import { mutation } from "./_generated/server"; import { v } from "convex/values";

                          export default mutation({
                          args: {
                              simpleArray: v.array(v.union(v.string(), v.number())),
                          },
                          handler: async (ctx, args) => {
                              //...
                          },
                          });
                          ```
    
  • Below is an example of a schema with validators that codify a discriminated union type: ```typescript import { defineSchema, defineTable } from "convex/server"; import { v } from "convex/values";

                          export default defineSchema({
                              results: defineTable(
                                  v.union(
                                      v.object({
                                          kind: v.literal("error"),
                                          errorMessage: v.string(),
                                      }),
                                      v.object({
                                          kind: v.literal("success"),
                                          value: v.number(),
                                      }),
                                  ),
                              )
                          });
                          ```
    
  • Always use the v.null() validator when returning a null value. Below is an example query that returns a null value: ```typescript import { query } from "./_generated/server"; import { v } from "convex/values";

                                export const exampleQuery = query({
                                  args: {},
                                  returns: v.null(),
                                  handler: async (ctx, args) => {
                                      console.log("This query returns a null value");
                                      return null;
                                  },
                                });
                                ```
    
  • Here are the valid Convex types along with their respective validators: Convex Type | TS/JS type | Example Usage | Validator for argument validation and schemas | Notes | | ----------- | ------------| -----------------------| -----------------------------------------------| ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | Id | string | doc._id | v.id(tableName) | | | Null | null | null | v.null() | JavaScript's undefined is not a valid Convex value. Functions the return undefined or do not return will return null when called from a client. Use null instead. | | Int64 | bigint | 3n | v.int64() | Int64s only support BigInts between -2^63 and 2^63-1. Convex supports bigints in most modern browsers. | | Float64 | number | 3.1 | v.number() | Convex supports all IEEE-754 double-precision floating point numbers (such as NaNs). Inf and NaN are JSON serialized as strings. | | Boolean | boolean | true | v.boolean() | | String | string | "abc" | v.string() | Strings are stored as UTF-8 and must be valid Unicode sequences. Strings must be smaller than the 1MB total size limit when encoded as UTF-8. | | Bytes | ArrayBuffer | new ArrayBuffer(8) | v.bytes() | Convex supports first class bytestrings, passed in as ArrayBuffers. Bytestrings must be smaller than the 1MB total size limit for Convex types. | | Array | Array] | [1, 3.2, "abc"] | v.array(values) | Arrays can have at most 8192 values. | | Object | Object | {a: "abc"} | v.object({property: value}) | Convex only supports "plain old JavaScript objects" (objects that do not have a custom prototype). Objects can have at most 1024 entries. Field names must be nonempty and not start with "$" or "". | | Record | Record | {"a": "1", "b": "2"} | v.record(keys, values) | Records are objects at runtime, but can have dynamic keys. Keys must be only ASCII characters, nonempty, and not start with "$" or "". |

Read the full file on GitHub · 676 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 4d ago First seen · 676 lines · 0 tokens per session scan A 2cbb87de5845

Subscribe to this mod's changes

convex-cursorrules-prompt-file is a cursor rule published in the GitHub repository PatrickJS/awesome-cursorrules (40,715 stars, last pushed 3mo ago), licensed CC0-1.0. It adds 6,270 tokens to every session, about $0.0314 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.