Generate Synastry Report (PDF or HTML)

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

Annotations declare readOnlyHint=false and openWorldHint=true but say nothing about billing, and the description fills exactly that gap with a concrete cost (5,000 credits, Tier 7), a budget-impact ratio, and a confirmation requirement. That is high-value behavioral context absent from structured fields. It stops short of saying what happens on failure (credit refund?) or whether rendering is synchronous.

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?

One dense sentence plus compact bracketed metadata; the cost warning is visible and the content list is front-loaded. Minor noise: the title promises 'PDF or HTML' while the description and schema expose no format parameter, a small internal mismatch.

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?

Output schema exists, so return shape need not be described, and the credit cost is disclosed. But with 4 parameters at 50% schema coverage, a nested whitelabel object, and many report siblings, the definition leaves localization, branding, and tool-selection questions unanswered.

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 50%, and the description contributes nothing parameter-level — the enumerated items (Big Three, aspect table) are output contents, not inputs. The two undocumented top-level parameters, language and whitelabel, are never mentioned, so an agent gets no help on localization or branding customization from the description.

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 ('Render') and resource ('relationship synastry PDF') and enumerates the exact document contents (Big Three side-by-side, top-40 cross-chart aspects, element/modality balance). An agent immediately knows what it produces, though it never differentiates itself from close siblings like astroway_reports_ai_synastry_narrative or astroway_relational_synastry.

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 bracketed cost note gives real usage guidance: premium tier, ~50% of free monthly budget, 'Confirm with user before invoking.' That is a genuine gating instruction. However, there is no routing guidance versus sibling tools — nothing says when to pick this PDF report instead of the synastry narrative report or the relational_synastry data endpoints.

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