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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds useful operational context the annotations lack: group, endpoint, and a 20-credit Tier 2 cost. It does not describe the coordinate space, units, or determinism of the layout, which would have been genuinely valuable for a layout-computing tool.

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 tight sentence plus three compact bracketed metadata lines; the purpose is front-loaded and nothing is wasted. Slightly terse given the amount of schema complexity being invoked.

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 no explanation, and the params are fully documented in the schema. The cost/endpoint metadata is a plus. The main shortfall is that it never clarifies that the input is natal data plus a dispositor mode, leaving the agent to infer the call shape entirely from the schema.

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 every parameter in depth (timezone, ayanamsa, houseSystem, fields, precision). The description adds nothing about parameters, so the baseline 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 verb (Return) and resource (disposition chains) plus the distinguishing output feature: computed x/y layout coordinates for graph visualization. This differentiates it from the sibling astroway_dignities_disposition_chains without naming it, since the layout-coordinate qualifier is the differentiator, but the separation is left implicit rather than stated.

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?

No when-to-use, when-not-to-use, or alternative routing is given. The phrase 'for graph visualization' implies the intended consumption context, but the agent is not told when to pick this over the plain disposition-chains sibling or the render_* tools.

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