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

Annotations already declare readOnly, idempotent, non-destructive, openWorld, so safety is covered. The description adds genuinely non-structured behavior: results are limited to the sync-linked systems, up to 50 records per call, and the return includes the record type each copy became in the other system. It stops short of discussing failure modes (unsynced record, partial links) or what happens when fewer than 50 are found.

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 usage trigger and packed with useful routing information, but the second sentence is long and clause-heavy, mixing return behavior, prerequisites, and the exclusion in a single breath. Slightly tighter segmentation would improve scanability; no sentence is wasted.

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 restated, and the description still flags the key return concept (the record type each became). Combined with the sync-link precondition and the get_record follow-up, an agent has everything needed to call this correctly and interpret results.

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%, so all three parameters are already documented in-schema (including the 'never pick one yourself' guidance for system). The description only reinforces the 50-record cap and the one-system scope, adding little beyond the schema. Baseline 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 first clause names a specific verb and resource ('find the same records in the customer's other systems') and immediately contrasts it with the sibling list_related_records for intra-system links. An agent can distinguish this from get_record, search_records, and list_related_records without opening any schema.

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?

It gives explicit when-to-use examples (won deals with no invoice, contact-to-customer mapping), an explicit exclusion ('Not for what a record is linked to inside one system (use list_related_records)'), and a prerequisite ('Only systems CRM Connector syncs with each other know their shared records'). It also routes the follow-up read to get_record.

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