get_cache_info

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

Goes beyond readOnlyHint=true by disclosing that the tool reads a local cache that may not contain complete transaction history, and by defining what a "degraded" decode_health status means (documents dropped on schema validation). A useful caveat about the remediation path (refresh_database) is missing, but the data-quality semantics are well disclosed.

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?

Three sentences, front-loaded with what the tool returns before the usage hint and the caveats. The parenthetical explaining decode_health is dense but earns its place by preventing misinterpretation of returned fields.

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?

There is no output schema, so the description carries the return-value burden, and it names the key fields (date range, count, per-collection decode_health) along with their interpretation. The only meaningful omission is guidance on what to do when the cache is incomplete or degraded.

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?

The tool takes zero parameters, so the baseline is 4; there is nothing for the description to compensate for and it makes no claims about inputs that could mislead.

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 and resource: reports cache metadata (date range of cached transactions, total count) plus decode_health counters. This is clearly distinguishable from sibling data-fetching tools like get_transactions because it describes availability metadata rather than transaction records, though it never explicitly names those siblings.

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?

"Useful for understanding data availability before running historical queries" gives a concrete when-to-use trigger. It stops short of explicit alternatives or exclusions — notably it never points to refresh_database when the cache is found to be stale or incomplete.

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