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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds substantive behavior beyond them: the dataset covers 53 countries, it will never silently return a US number, it is honest when a country is missing, and it falls back to the local emergency-number rule. It also sequences its output relative to pastoral content ('point to Christ only after the line is given').

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 with the priority directive and the trigger condition, which is exactly what an agent needs first. It is somewhat long and includes pastoral framing ('the Word and the family', 'point to Christ only after') that is not strictly selection-critical, but nothing is wasted outright.

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?

For a single-parameter lookup with an output schema, the description is complete: trigger conditions, precedence, country handling, missing-country fallback, and output ordering are all covered. Return format is left to the output schema, which is appropriate.

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 coverage is 100% and the schema already documents the country parameter (name or ISO alpha-2, ask if unknown). The description largely repeats this, though it reinforces the operational imperative to ask before returning any number, which is a slight addition over the schema text. 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+resource: returns the real emergency number and crisis line for a given country. The scope (53-country shipped dataset, never a US default) and its priority over all siblings are unmistakable, so an agent can distinguish it from tools like a_prayer_for or the_gospel at a glance.

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 states when to invoke it ('When a person speaks of harming themselves or someone else, or is in danger') and its precedence ('THIS COMES FIRST'). It also gives concrete trigger utterances and an alternative path when the country is unknown (ask the person first), plus the fallback general rule when a country isn't held.

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