Explain case

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

Annotations already declare read-only, idempotent, non-destructive, closed-world behavior, so the description is free to add value — and it does, disclosing determinism, an 8-15 line bound, markdown format, and that citations are embedded. With no output schema, this is the only place the return shape is described; only error behavior (e.g., unknown case_id) is unstated.

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?

Two sentences, no filler. The output specification comes first and the citing directive last, both of which earn their place for a tool whose whole value is a quotable narrative.

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 two-parameter read-only tool with full schema coverage and no output schema, the description covers format, length, determinism, and citation content — enough to call it and use the result correctly. The remaining gap is positioning against the very similar ghost_summary/ghost_get_case siblings.

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 100%, including the mask flag's effect ('mask e-mails, phones and names') and an example value for case_id. The description adds no parameter meaning beyond the schema, so the baseline of 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?

The description names the resource (one decision/case) and precisely characterizes the output: a deterministic 8-15 line markdown narrative with evidence/activity citations. That is far more specific than a restatement of the title, but it never distinguishes this from ghost_summary or ghost_get_case, so an agent must guess how the narrative differs from a summary.

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 only guidance is a downstream instruction ('Quote it, do not paraphrase facts'), which governs how to consume the output, not when to call this tool. There is no statement of when to choose ghost_explain_case over ghost_summary or ghost_get_case, and no prerequisites or exclusion cases.

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