set_metadata

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

With no annotations provided, the description must fully disclose behavioral traits. It only says 'sets a metadata value' but does not explain whether it overwrites an existing key, what happens if the key is invalid, whether the operation is reversible, or any error conditions. The mutation side effects are implied but not detailed, leaving the agent to guess.

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, concise sentence that uses the standard 'Sets [resource] on [object]' structure. It is front-loaded with the verb and resource, contains no filler, and earns its place. Ideal length for a simple setter.

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?

Given the simplicity of the tool (3 string params, no nested objects), the description is adequate but minimal. It does not mention how the metadata key is defined, whether values are limited to strings (though schema implies), or what the return value is (no output schema). With no annotations, the description could have provided more context about side effects or use cases, but the tool is straightforward enough that the current level might be marginally acceptable.

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 input schema has 100% description coverage, so each parameter (key, value, projectItemId) is already documented. The description adds no additional meaning beyond that—it merely restates that it sets a value. Since the schema handles parameter documentation, a baseline score of 3 is appropriate; no extra context is provided.

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 clearly states the action (sets) and the resource (project metadata value on a project item). It is specific enough to distinguish from similar tools like get_metadata, but it does not explicitly differentiate from set_project_panel_metadata or add_custom_metadata_field, which also deal with metadata but in different contexts. The verb and resource are unambiguous.

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 this tool versus alternatives. There is no mention of prerequisites, whether keys must already exist, or how to obtain projectItemId. The description gives no indication of when this tool is appropriate or when another metadata-related tool (e.g., add_custom_metadata_field, set_project_panel_metadata) should be used instead.

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