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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so safety is covered. The description adds genuine behavioral context beyond that: the underlying source (FJC directory), the fact that results include name, court, commission date and current service status, and that counts are broken out by court level.

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 compact sentences, front-loaded with what is returned before the illustrative queries. No wasted filler, though the trailing list of example questions is slightly redundant with the examples already embedded in the input 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 carry return-value meaning, and it does: appointee fields plus per-court-level counts. Combined with annotations covering the safety profile, an agent has everything needed to call this 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 description coverage is 100%, so the schema already documents president, court_type and limit (including defaults and max). The description only indirectly reinforces court level via the counts-by-court framing; baseline 3 applies when the schema carries parameter meaning.

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 (list) and resource (Article III federal judges appointed by a US president) plus the data source, the FJC directory. It is clearly distinguishable from its siblings fjc_judge_lookup and fjc_judges_by_court, which are keyed on judge/court rather than president.

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?

The example questions ("how many judges did Biden appoint", "Trump appellate appointees") clearly indicate the intended use case, so the agent knows when to reach for it. It does not, however, explicitly name the alternative for court-centric queries (fjc_judges_by_court), leaving sibling selection to inference.

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