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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds non-obvious interpretive context: results are confined to STRAELO's confirmed coverage rather than the vendor's global customer base, and an empty result must not be read as the vendor having no customers. It also discloses returned evidence/confirmation timestamps and normalization/deduplication behavior, which materially affects how the agent should trust and present results.

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?

Front-loaded with the core operation, then the coverage caveat, then bolded routing blocks — well structured and mostly earn-your-place. Some repetition of 'currently confirmed' and 'STRAELO coverage' across sentences costs a point but doesn't obscure anything.

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 an output schema (so return shape needn't be described), full schema coverage, and strong annotations, the description supplies exactly what structured fields cannot: coverage limits, empty-result semantics, and sibling routing. Nothing an agent needs to call and interpret 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?

Schema description coverage is 100%, with the limit and vendor parameters fully documented in the schema (max 100, no pagination, canonical name normalization). The description adds no parameter-level meaning beyond that, 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?

States a specific verb and resource ('Retrieve confirmed customer domains currently using a specified vendor') plus the data source (STRAELO's persisted CSI coverage). It explicitly bounds the result set (only confirmed PRESENT relationships, normalized and deduplicated), which distinguishes it from the detection and history siblings.

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?

Provides explicit USE WHEN and DO NOT USE WHEN blocks, naming three concrete alternatives (customer_vendor_detection, vendor_customer_adoption_change_lookup, vendor_customer_transition_signal_lookup) with the condition that selects each. The direction of the lookup — vendor to customers, not customer to vendors — is unambiguous.

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