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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered. The description adds genuinely useful non-annotation context: the 10-credit Tier 1 cost and the fact that this is a Cursor-friendly alias of astroway_numerology_kabbalistic_strict_expression, which prevents duplicate calls.

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?

Purpose is front-loaded in the first sentence, followed by compact bracketed metadata for group, cost, and alias. No filler sentences; every line carries information an agent can act on.

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 an output schema present the description needn't explain return values, and annotations cover the safety profile. The remaining gap is the unexplained required 'date' parameter, but otherwise the definition gives enough to call the tool 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?

Schema description coverage is 50%: 'fields' and 'precision' are documented in the schema, but 'date' and 'name' are not. The description clarifies 'name' as the full birth name whose letters are reduced, but gives no explanation of why a date is required for an Expression calculation, leaving half the parameters under-specified.

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 ('Calculate the Expression (Destiny) number from full birth name letters') and names the system ('Kabbalistic (Mathers strict)'), which separates it from the Chaldean/Pythagorean/Vedic siblings. The computation method (all letters reduced) also distinguishes it from soul_urge/personality, though it never names a sibling it is not.

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?

Usage is implied by the calculation described and the group/cost metadata, but there is no explicit when-to-use, when-not, or routing to the canonical sibling. An agent must infer that this is the kabbalistic-strict variant versus the plain kabbalistic or chaldean Expression tools.

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