check_table_freshness

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), but the description adds genuinely new context: it reads metadata only and scans no data, so the agent knows there is no cost or data-scan risk. It explains the failure mode it detects (silent stale data) but says nothing about the shape or size of the report.

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 and the motivating problem, then the arguments. The middle rationale paragraph is slightly longer than strictly needed but earns its place by justifying when to call the tool.

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 three-parameter, read-only metadata tool with no output schema, the definition covers purpose, trigger, cost profile, and every argument. The one gap is that it never hints at what the freshness report contains, which an agent would have to discover at runtime.

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 0%, so the description carries the full burden and does so well: dataset_id gets a concrete example, table_id is explained including the omit-to-report-all behavior and why that is preferred, and environment documents the default plus the list_environments route. All three parameters gain meaning beyond the bare schema types.

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 ('report when tables were last written') and immediately frames the goal ('to catch stale or dead sources'). This distinguishes it from siblings like list_tables and get_table_schema, which enumerate structure rather than freshness.

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?

Gives an explicit trigger ('Check before trusting a table you have not used before') and a routing hint ('Call list_environments to see what exists') for the environment argument. It does not name a sibling alternative for the general case, which keeps it just shy of a 5.

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