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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false, and destructiveHint=false, so the safety profile is covered. The description adds real value beyond that by disclosing exactly what payload comes back (eight named facts plus prose and a URL), which effectively substitutes for the absent output schema. It stops short of stating freshness, caching, or coverage gaps for unusual jurisdictions.

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?

A single dense sentence that front-loads the purpose and follows with the returned fields; every clause names a distinct datum rather than padding. It is long, but the length is justified by enumerating eight return values for a tool with no output schema.

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 one-parameter read-only lookup with no output schema, the description is nearly self-sufficient: it tells the agent both the input scope (US state) and the complete return set. The only real gap is the absence of guidance on how this relates to the county/institution guide siblings, which would help an agent route correctly.

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% and the single 'state' parameter already documents all three accepted formats ('CA', 'California', 'california') in the schema itself. The description adds nothing beyond confirming the parameter is a US state, so the baseline 3 for fully-documented schemas 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 (Get) and a precise resource (high-level probate facts for a US state), then enumerates the exact facts returned: threshold, filing deadline, creditor-claim period, timeline, fees, UPC/community-property/independent-administration status, prose overview, and guide URL. This clearly separates it from siblings like lookup_county_guide, lookup_institution_guide, and get_estate_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?

Usage is only implied: the word 'state' plus the enumerated state-level facts signal this is the state-scope lookup rather than a county or institution guide, but the description never says when to prefer it or names any alternative. No exclusions, prerequisites, or routing logic are given, so an agent must infer the boundary from the sibling list.

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