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

Annotations already declare readOnly/openWorld=false/destructive=false, but the description adds real context: newest-first ordering, the cursor-to-nextCursor pagination contract, and how date-only vs timestamp `to` bounds are interpreted in UTC.

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-loads the core purpose in the first clause, then layers filters, date semantics, and pagination without redundant restatement of schema 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?

With 7 optional params, an output schema present, and read-only annotations, the description covers ordering, filtering, date interpretation, and pagination—everything an agent needs to call and iterate 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 coverage is 100%, so the baseline is 3; the description nonetheless adds value by defining the UTC interpretation of dates, the inclusive whole-day behavior of a date-only `to`, cursor provenance, and minor-unit currency amounts—semantics not fully captured by the schema property descriptions.

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 ('List the user's travel expenses') plus ordering, and is clearly distinguishable from the sibling mutation tools (log_expense, update_expense, delete_expense) and from get_travel_summary.

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?

Explains the filtering levers (date-range, currency, journey/stay attachment) and the pagination flow with `cursor`/`nextCursor`. It does not explicitly route against alternatives like get_travel_summary, which keeps it just below a 5.

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