switch_source

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and does so well: it discloses the single-active-source invariant, that all queries run against the active source, that each source has distinct fields, and that the previous schema is invalidated after the switch. It stops short of describing error behavior or whether the switch is reversible.

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?

Front-loaded with the core action, then the invariant, then the required follow-up, then the allowed values. Each sentence earns its place, though the final enumeration of sources partly duplicates the schema enum.

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?

For a no-annotation, no-output-schema mutation tool this is nearly complete: purpose, invariant, and required follow-up call are all covered. Missing only details such as return value or error/side-effect behavior for invalid names.

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?

Schema description coverage is 100% and the enum already constrains the source values, so the schema does the heavy lifting. The description restates the source names but adds no format or semantics beyond what the schema and its enum provide; baseline 3 is appropriate.

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?

States a specific verb (cambia/cambiar) and resource (fuente de datos activa), and clarifies the singular-active-source model. It also implicitly distinguishes itself from siblings by naming get_schema as the required follow-up, so an agent can tell it is the state-changing tool rather than a query or schema tool.

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?

The description gives a clear trigger (when you need to change the active data source) and an explicit post-condition workflow: after switching you must call get_schema again because the old schema is invalid. It does not name alternatives or when-not-to-use cases, but the sequencing guidance is strong.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.