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

Annotations already declare the safety profile (readOnlyHint=false, openWorldHint=true, idempotentHint=false, destructiveHint=false), so the bar is lower. The description still adds meaningful context beyond them: the 5,000-credit Tier 7 cost, the ~50% budget impact, and an explicit instruction to confirm with the user before invoking, plus the default 300 km line radius. It is silent on whether the output is cached or regenerated, which keeps it from a 5.

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?

Dense but front-loaded: format/scope first, then per-place contents, then cost. Every clause carries information. It is docked slightly because the text trails off mid-sentence ('a…'), leaving an unfinished clause rather than a clean close.

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 restated, and the description helpfully covers report contents and cost. But for an 8-parameter premium tool with 38% schema coverage, the omission of language, categories, whitelabel, precision, and fields leaves real gaps an agent must guess at.

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 only 38%, so the description must carry the load, and it largely does not. It hints at the locations cap ('up to five places') and the 300 km line radius (relating to orbKm), but never names or explains orbKm, categories, language, fields, precision, or whitelabel. The '?format=html' instruction does not even correspond to a schema parameter, which risks confusing an agent about how format is actually selected.

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 concrete operation on a concrete resource: comparing up to five places against one birth chart to produce a relocation report in PDF or HTML. The enumerated contents (relocated ascendant/midheaven, planets changing house, astrocartography lines within 300 km) are unmistakably relocation/astrocartography material, so an agent can tell this apart from the natal, synastry, or transit report siblings 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?

Provides the format-selection rule (PDF by default, add `?format=html`) and a strong invocation caveat (premium cost, confirm with the user first), which is real usage guidance. However it never says when this report is preferable to the neighbouring report tools, so alternative-routing is left to inference.

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