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

Annotations already cover read-only, idempotent, non-destructive, and closed-world behavior. The description adds the profection calculation rule, required birth time, default target_date as today (UTC), output scope up to twelve profection years, and a pointer to the full error contract. It stops short of operational details like rate limits or auth, so 4 rather than 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?

Front-loads the purpose, then uses clear WORKFLOW, INPUT CONTRACT, and DO NOT CONFUSE WITH sections. Every sentence adds routing or usage value; the rule formula is compact and explains the output logic without bloat.

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 the description need not detail return values, yet it still covers the key outputs and the input contract. Combined with workflow, sibling disambiguation, and an error-contract link, it is complete enough for an agent to invoke correctly without opening 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 baseline is 3. The description adds a meaningful semantic detail not in the schema: target_date defaults to today (UTC) rather than null. It also reiterates required birth time, but most parameter format details remain in the schema.

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 and resource ('Annual profections for a birth chart and a date') and enumerates the outputs: activated whole-sign house, its sign, lord of the year, natal placement of the year lord, and next twelve profection years. It also names sibling tools it is not, clearly distinguishing it from dasha and solar return.

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?

Explicitly gives BEFORE (asterwise_get_western_natal) and AFTER (asterwise_get_western_transits_monthly) workflow steps, and a DO NOT CONFUSE WITH section naming two alternatives with reasons. The input contract adds when the birth time is required and how target_date defaults.

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