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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds a genuine privacy trait beyond that: excerpts are opt-in sharing and "never a name they did not choose to show" — useful for an agent handling sensitive personal narratives.

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?

Reasonably front-loaded, but the parenthetical enumerating returned fields is largely redundant since an output schema exists, and the sentence is dense with nested clauses. It reads more like marketing copy than invocation guidance.

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, return values need not be explained, and the privacy/opt-in nuance plus matching scope give the agent enough to call it correctly. Minor gaps remain around no-match behavior and the `limit` parameter.

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 50%: `word` is documented, `limit` is not. The description reinforces that `word` is matched against excerpt text ("a word to look for in the excerpts") but adds nothing about `limit` semantics, default 8, or whether omitting `word` returns everything. 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 resource (testimonies) and what it retrieves, plus the fields returned via `get_testimony_wall` (excerpt, journey word, city). It is clearly distinguishable from generic search tools, though it does not name a sibling tool to contrast against.

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 quoted user phrasings ("has anyone found faith after addiction", "someone who came back after years away") give concrete intent cues for when to reach for this tool rather than scripture or devotional siblings. However, it names no alternative tool and gives no when-not-to-use condition.

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