add_costs

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

With no annotations, the description carries the full burden of explaining behavior. It states that time is logged, but does not disclose whether a new entry is always created, what the response is, whether duplicate logs are allowed, or any permission requirements.

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 a single, efficient sentence with no filler or repetition. It front-loads the core action, though it is so brief that it misses opportunities to add useful context.

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 mutating tool with 7 parameters, no annotations, and no output schema, this description is under-specified. It lacks guidance on return values, when to use alternatives, and expected side effects, leaving the agent to rely heavily on the schema and tool name.

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 already provides descriptions for all 7 parameters, including constraints, defaults, and optionality. The description adds only the phrase 'optionally money,' which is already reflected in the money parameter's null default. Baseline 3 is appropriate given high schema coverage.

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 states a clear action—logging time and optionally money—against a task, which maps directly to the tool name. It distinguishes itself from read-oriented siblings like get_costs by implying a write/insertion operation, though it does not explicitly call out sibling tools.

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?

No guidance is provided on when to use add_costs versus update_costs or get_costs. An agent must infer that this creates a new cost entry and that update_costs would be used for modifying existing ones.

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