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

Annotations already declare readOnly/idempotent/non-destructive and closed-world, so the safety profile is covered. The description adds substantive behavior: results are numbers only (no individual postings, no map), values are rounded on the website as 'über X', newly-discovered is a 7-day window with trend versus earlier days, and the counted region must be stated explicitly in the answer.

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?

A single, densely packed sentence with no filler and the core purpose front-loaded. Readability suffers slightly from three levels of nested parentheses around the output-field names, but every clause carries information.

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?

An output schema exists, so return values need not be explained, yet the description still maps the key fields (kanal_bezeichnung, zaehlung, je_kanal_summen.personaldienstleister). Combined with scope, default, exclusions and the sibling alternative, nothing needed to invoke 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 description coverage is 100% and the enum for gebiet already documents Germany as default and DACH as the exception. The description adds only the instruction to name the gebiet field in the response, which is marginal beyond the schema; baseline 3 is 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?

States a specific verb+resource+scope: counts of active jobs across the whole market, without title or location, defaulting to Germany. It explicitly contrasts itself with stellen_finden, so an agent can separate the two without opening either 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?

Gives an explicit routing rule: use this for general job-market questions or comparisons; for a specific position or region use stellen_finden, whose channels are directly comparable. Both the when and the alternative are named.

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