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 marginal bar is lower. The description still adds real traits: results are bounded, carry canonical source URLs, are capped at 20 indexed Scripture references, and session-derived profiles are gated behind provenance verification — none of which is in the annotations or schema.

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?

Three sentences, front-loaded with the core action and followed by a scoping caveat and a result-shape preview. Every sentence carries information, though the provenance sentence is dense and slightly jargon-heavy for what is a simple single-parameter lookup.

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 values need not be explained, yet the description usefully previews their boundedness and the 20-reference cap. For a one-parameter, non-destructive read tool with full annotation coverage, nothing an agent needs to invoke it correctly is missing.

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?

There is a single parameter with 100% schema description coverage, and the schema already explains the ID's origin (search_msza_ai sourceId or get_sermon.references ids). The description only restates the 'exact public person ID' constraint, adding the 'exact' qualifier but no new format or derivation detail beyond 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 ('Returns one curated Catholic or biblical person profile') and bounds it by an exact public person ID. The scope qualifier 'curated ... public' distinguishes it from the session-derived profile variant that the next sentence declares unavailable, so an agent can tell what entity this tool resolves without ambiguity.

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?

Gives a concrete usage precondition ('by exact public person ID') and an implicit exclusion: session-derived dynamic profiles are unavailable. It does not name a sibling tool as an alternative route to person data, so it stops short of full when/when-not/alternatives routing.

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