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

Even though annotations already mark the tool as read-only, idempotent, and non-destructive, the description adds meaningful behavioral detail: chains are reconstructed, carry confidence and link method, and deliberately exclude high-fan-out administrative umbrellas. This prevents an agent from wrongly assuming every reference relationship is merged into the chain.

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?

The description is front-loaded with the core definition and chain example, then the source of chain_id, then the important boundary condition. The third sentence is long but earns its place by preventing a costly misuse of the tool. Nothing in the description is redundant with the schema or annotations.

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 tool with an output schema and strong annotations, the description covers the main purpose, how to get the identifier, what the result represents, and a critical exclusion rule. An agent has enough context to invoke it correctly without further investigation.

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?

The schema only defines chain_id as a required string with zero coverage, but the description compensates by explaining where to obtain a valid value: from the chain_id field of any act. It does not give format examples or edge-case guidance, but for a single opaque identifier this is sufficient and actionable.

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 a specific resource (a reconstructed procurement lifecycle chain), a retrieval action by chain_id, and explicitly contrasts a chain with mere act references, which distinguishes it from sibling tools like get_act. It also gives a concrete example of the chain shape (commitment → award → contract → payments), leaving no ambiguity about what the tool returns.

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 tells the agent exactly when to call it: when you have a chain_id, obtained from the chain_id field of any act. It also explains when not to expect a chain — for broad administrative umbrella references cited by more than 25 acts — and directs the agent to the act's own references instead, which is an explicit alternative routing.

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