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

Annotations already provide readOnlyHint=true, so the read-only nature is known. The description adds valuable behavioral context: it returns real prayers with NIV passages and links, and routes crisis users to 988. No contradiction with annotations.

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?

The description is front-loaded with the core purpose and uses four efficient sentences. It is slightly redundant with the schema's enum values, but each sentence earns its place by adding audience, usage, return, and safety information.

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?

Given two optional parameters, readOnly annotation, and no output schema, the description is quite complete. It specifies what is returned (prayers with Bible passage and link), who it's for, and the crisis-handling behavior. Minor omissions like time zone or pagination are not relevant here.

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% (both topic and feeling are described). The description adds value by offering examples of how to phrase 'feeling' in the user's own words ('I am so angry at God') and clarifies that either a feeling or topic can be given. This goes beyond the schema's basic descriptions.

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?

The description clearly states the tool's function: 'Find an honest scripture prayer for what someone is feeling after leaving the church.' It names a specific resource (prayers from Sanctuary) and distinct audience, which differentiates it from siblings like find_house_church and list_prayer_topics.

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?

The description provides explicit usage context: when to use (for people leaving the church with feelings like broken trust, anger, etc.) and a clear when-not ('Not counseling; anyone in crisis is pointed to 988'). However, it does not explicitly mention alternative sibling tools, so it stops short of a 5.

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