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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the remaining burden is light. The description adds genuinely useful behavior: the list is fixed with stable ids, and downstream tools reference those ids, which is non-obvious and important for chaining. It does not discuss pagination or size of the payload, a minor gap.

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-loaded one-sentence purpose followed by labeled blocks (WORKFLOW, INPUT CONTRACT, DO NOT CONFUSE WITH). Every line carries information; nothing is padding despite the structured formatting.

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-value documentation is not required. For a zero-required-input reference lookup, the description covers provenance, id stability, workflow placement, and sibling disambiguation — everything needed to call it correctly.

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?

Only one parameter (response_format) and schema description coverage is 100%, so the schema already documents the enum and default fully. The description adds only 'No inputs beyond response_format', which is a restatement rather than new meaning. Baseline 3 is appropriate.

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: returns what each house and planet signifies in a named classical text (BPHS), as a fixed list with stable ids. It also cites the exact source chapters/verses, which pins down the content precisely and separates it from the sibling western significations list.

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?

Explicit workflow framing (BEFORE: none, standalone; AFTER: asterwise_get_vedic_daily_factors, which cites these ids) tells the agent where this fits. The DO NOT CONFUSE WITH block names two alternatives and gives the distinguishing reason for each, so selection vs. siblings is unambiguous.

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