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

Beyond the annotations (read-only, idempotent, closed-world, non-destructive), it discloses substantive operational facts: a shared quota of 3 answers per chart per 6 hours across chart_overview and current_chapter, and a privacy guarantee that birth details are used only for calculation with a one-way code retained 6 hours. It adds no note on what happens when the quota is exhausted or whether repeat calls return identical output.

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?

Contents are front-loaded with the output payload first, then areas, then limits and privacy. The long enumeration of returned findings is dense but earns its place given there is no output schema; wording is compact with no filler sentences.

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?

With no output schema, the description carries the return-value burden and does so thoroughly, covering payload shape, allowed areas, the health exclusion, quota sharing with siblings, and data retention. An agent can decide whether to call it and what to expect without further information.

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 all four parameters are already documented in the schema, including the area enumeration and place_token provenance. The description adds no format, range, or constraint detail beyond what is structured, so the baseline of 3 applies.

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 resource ('plain-language findings from the birth chart for one area of life') and enumerates exactly what comes back: house strength, ruling planet and its position, supporting planets, and current-chapter relevance. It also enumerates the eight valid areas and rules out health. The only gap is that it never contrasts itself with chart_overview or current_chapter, which it mentions solely in the quota sentence.

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?

Lists the selectable areas and explicitly excludes health, which is useful when-not guidance. But it gives no direction on choosing between this and chart_overview (whole chart) or current_chapter (chapter detail) despite naming both, so the agent must infer the selection rule from sibling names.

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