Lists all schemas in a PostgreSQL database or all databases in MongoDB for the selected connection, so you can inspect available namespaces before querying.
List all schemas in the database (MongoDB: lists the databases)
| Name | Required | Description | Default |
|---|---|---|---|
| connection | No | Nome ou alias da conexão (veja list_connections). Se omitido, usa a conexão ativa ou a padrão. |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
readOnlyHint=true already tells the agent this is a safe, non-mutating read, so the bar is lower. The description's only added behavioral value is the MongoDB/database equivalence note; it says nothing about permissions, result ordering, or size limits.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
One short sentence with the core purpose front-loaded and a parenthetical dialect note appended. No filler or redundancy.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
An output schema exists and annotations cover the safety profile, so return values and mutability need not be explained. What is missing is the relationship to list_objects and the fact that the connection argument can target a non-default database, which matters for a tool in a multi-connection server.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
There is a single optional parameter with 100% schema description coverage, including its default and fallback behavior, so the schema fully carries parameter meaning. The description adds nothing about the connection parameter, which is acceptable at this coverage level.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description pairs a specific verb (List) with a specific resource (all schemas in the database) and adds a dialect clarification that MongoDB returns databases. It is clear on its own, but it does not distinguish itself from the sibling list_objects, which an agent could easily confuse it with.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Usage is only implied: an agent can infer this is the discovery call that precedes list_objects/get_object_details, but the description never says when to prefer it or when to use list_objects instead. No prerequisites or exclusions are stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.