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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and non-destructive behavior, so the safety profile is well covered. The description adds only that the series ID is raw and gives examples; it omits behavior such as default date ranges, return format, or how start_year/end_year affect the fetched time series.

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?

The description is two tightly written sentences with no wasted words. The core capability and usage condition are front-loaded, making it easy for an agent to parse quickly.

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 simple lookup tool with rich annotations, the description covers what the tool does and when to use it. However, because there is no output schema, it should ideally explain what the fetched time series returns or how start_year/end_year defaults work, leaving a moderate completeness gap.

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 schema already documents all three parameters. The description's mention of 'raw series ID' and example IDs adds slight meaning beyond the schema, but it does not elaborate on start_year or end_year semantics, making the baseline 3 appropriate.

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 states a specific verb and resource: 'Fetch any BLS time series by its raw series ID.' It distinguishes the tool's input mode from likely siblings by emphasizing exact 'raw series ID' usage and provides concrete examples such as 'LNS14000000'.

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 clearly states when to use the tool: 'For when you know the exact BLS series ID.' However, it does not name an alternative for when the exact ID is unknown, such as a search or indicator-based sibling tool.

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