CrabTalk vs Convex.
Functions + reactive database
CrabTalk gives each tool call a small, explicit memory budget and service-owned SQLite. Convex combines TypeScript functions, a reactive database and components for agents and MCP.
Which fits your work?
CrabTalk
- Small, independently budgeted tool calls
- SQL shared across several agents
- A Rust/Wasm service fits the workload
Convex
- A live UI with reactive subscriptions
- A TypeScript application backend
- Agent components alongside application data
Capabilities side by side.
| Capability | CrabTalk | Convex |
|---|---|---|
| Memory allocation | 1–128 MiB budget per tool | Actions: 64 MiB Convex runtime or 512 MiB Node.js |
| Per-call sizing | Code can lower one call’s memory reservation | Action allocation follows the selected runtime |
| Data model | Service-owned SQLite and SQL | Documents, indexes and reactive queries |
| Transactions | One transaction per tool call | Queries and mutations are transactional; actions call them |
| MCP | Hosted discovery and tool calling | MCP component with tools and OAuth |
| Client updates | Agents call tools for current results | Subscriptions automatically update connected clients |
| Runtime | Rust compiled to WebAssembly | JavaScript or TypeScript; optional Node.js actions |
A support inbox shared by agents and people.
An agent records incoming tickets and a teammate reviews them. Choose whether tool access or a live application UI is the center of the workflow.
CrabTalk
- Define ticket tools and SQLite migrations
- Set a memory budget for each tool
- Connect agents to the deployed service
Convex
- Define ticket documents, queries and mutations
- Add agent actions or the MCP component
- Subscribe the review UI to ticket queries
CrabTalk vs Convex pricing.
CrabTalk
Runs, CPU, reserved memory over time and database rows. A call can lower its memory budget before doing smaller work.
Convex
Function calls, action compute, database storage and bandwidth. Rates and included usage depend on the plan and runtime.
The chart models Professional action rates. Convex Business runtime billing differs; choose the plan and include subscriptions and database traffic in a full estimate.
Limits that affect the choice.
- CrabTalk tools have at most 100 ms CPU and 128 MiB memory. Larger Node.js dependencies or compute-heavy actions may favor Convex.
- Convex actions access the database through queries and mutations. An external API call and a later mutation are separate operations.
- CrabTalk provides SQL tool results. Convex provides reactive application queries; replacing a subscribed UI requires more than porting tool handlers.
Questions about CrabTalk and Convex.
Can Convex expose tools to external agents?
Yes. Its MCP component turns application functions into remote tools with OAuth. Its agent component also supports tool use within Convex applications.
Is precise memory exclusive to CrabTalk?
Memory control exists elsewhere. The distinction here is CrabTalk’s 1–128 MiB tool budgets and the ability to lower one running call’s reservation.
Can I move a Convex database directly to CrabTalk?
No. Convex documents and reactive functions need a SQL schema and Rust tools. Account for client subscriptions and authentication when planning a port.
Sources.
Checked .