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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint, so safety is covered. The description adds value beyond that by enumerating the returned fields (in lieu of an output schema) and explicitly stating 'Returns no personal data', a privacy trait not captured by annotations. It stops short of describing error behavior for invalid codes.

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 purpose, then the parameter source, then the return contents — no filler sentences. The colons and clauses are dense but each carries distinct information; only the slightly run-on construction keeps it from a 5.

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?

With no output schema, the description compensates well by naming the returned fields and the privacy posture, and it explains the required credential. The one meaningful gap is the unresolved relationship with get_rental_status, an identical sibling, which the agent needs in order to route correctly.

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%, so the single parameter's type and length bounds are already documented. The description adds provenance ('the code from the browser checkout ... from create_rental, or from Galaxy Mind support'), which tells the agent where to obtain the value but adds no format or validation detail beyond the schema, so the baseline 3 applies.

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 names a specific resource (a Galaxy Mind rental) and states exactly what it returns: state, start/end, delivered TH, rigs online. It is clear what the tool does, though it does not carve out a distinct role versus the near-identical sibling get_rental_status — it only says the data is the same.

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?

It usefully tells the agent where the access code comes from (browser checkout at galaxymind.space/hashrate/rent, create_rental, or support), which is real usage guidance. It never says when to choose this tool over get_rental_status, which returns the same data, leaving the agent with no disambiguation rule.

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