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

Annotations already declare readOnlyHint=true, so the description's behavioral disclosure is less critical. However, the description adds value by noting it uses the GraphQL node query and listing return fields (amount, status, timestamps, order id, linked customer), providing useful context beyond the annotation.

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, extremely concise, with the verb and resource first, no wasted words. Every sentence adds value.

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 simple read-only tool with one parameter and no output schema, the description provides all necessary context: how to identify the transaction (global ID), what the tool does (fetch), and what data is returned (amount, status, etc.). No gaps.

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 already describes the 'id' parameter with 100% coverage. The description adds significant extra meaning: that it's the opaque GraphQL global ID (base64-looking), not the short legacy id, and gives an example of where to get it (from search result's node.id). This exceeds baseline.

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?

Description clearly states 'Fetch one transaction' using GraphQL global ID, distinguishes from sibling braintree_search_transactions which returns multiple, and explicitly notes it is NOT the short legacy id.

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?

Description explicitly says to use the GraphQL global ID from braintree_search_transactions results and warns against using short legacy id. It clearly indicates when to use this tool (when you have a global ID to fetch a single transaction), but does not explicitly state when not to use it.

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