List cost codes

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds non-obvious behavior: only ACTIVE cost codes are returned, and the exact fields in the response. It does not mention result volume, ordering, or pagination, which keeps it at 4.

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 short paragraphs, no wasted words, and the identifying information comes first. The second paragraph is slightly telegraphic ('Every active cost code with its code number, name and parent group') rather than smoothly integrated, but it is efficient overall.

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?

With no output schema, the description usefully enumerates the returned fields and the active-only filter, and annotations cover safety. For a zero-required-parameter list tool this is nearly complete; only ordering/result-size expectations are unaddressed.

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 coverage is 100% and the single 'search' param is fully documented there. The description's 'search narrows by code or name' essentially restates the schema description ('Matches the code or the name') with only a mild addition ('narrows' implying subset filtering). Baseline 3 is appropriate.

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?

Names the resource (company cost codes), its fields (code number, name, parent group), and its role (attaching to estimate, change order and invoice items). The line 'cost_code_id is what the item tools take' distinguishes it from the sibling item tools (add_estimate_items, add_change_order_items, add_invoice_items). It stops short of explicitly naming an alternative tool to use instead, keeping it at 4.

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?

The phrase 'to put on estimate, change order and invoice items' plus 'cost_code_id is what the item tools take' gives the agent a concrete pre-requisite workflow: call this before the item-adding tools. No explicit exclusions or when-not conditions are given, so it falls short of 5.

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