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

Annotations already declare readOnly/idempotent/non-destructive, so the burden is light. The description still adds real value beyond them: the data source (BLS PPI schedule page), the shape of the return (next date plus up to 12 following dates), the time zones returned, and a credit cost. It stops short of saying what happens when the schedule page is unreachable or how stale the cached data may be.

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 as a plain question the tool answers, followed by return shape, data source, scope exclusion, and cost in that priority order. Every sentence carries distinct information; nothing is repeated from the name or schema.

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 must describe return values, and it does: next release date/time in three zones, reference month, and up to 12 following dates. For a single optional-parameter, read-only lookup, nothing an agent needs in order to call it correctly is missing.

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% and the timezone parameter is already documented there, so the baseline would be 3. The description adds meaning beyond the schema by explaining that the parameter drives a third 'your time zone' field alongside always-present US Eastern and UTC fields, clarifying the parameter's effect on output rather than just its format.

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?

Names a specific resource (US PPI release schedule) and a specific question it answers, and distinguishes itself from the many other release-date siblings (next_cpi_release, next_gdp_release, next_jolts_release) by naming the exact index. An agent can route to it without opening the schema.

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?

Explicitly bounds scope with 'Gives dates only, not the index values', which tells the agent when this tool is insufficient, and flags the 1-credit cost so the agent can weigh alternatives. It does not name a sibling to use for actual index values, so the routing is implied rather than explicit.

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