add_marker

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

No annotations are provided, so the description carries the full behavioral burden. It clearly states that the operation is an addition and that the target sequence need not be active, which are useful behavioral details. However, it does not disclose side effects, failure behavior, return value, or whether adding a marker will modify the saved project state in a significant way.

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 two short sentences with no filler. It front-loads the core action, adds the non-active-sequence nuance, and does not waste any words. Every sentence earns its place.

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 tool with six parameters and full schema descriptions, the description is reasonably complete for invoking the operation. However, because there is no output schema and no annotation context, the agent still lacks information about what the call returns, whether it can silently fail, and what happens when the sequence is invalid or missing.

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 covers all six parameters with detailed descriptions, so the description itself does not need to redefine them. The description adds no parameter-level meaning beyond the schema, but because schema coverage is 100%, the baseline score of 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?

The description clearly states a verb and resource: 'Adds a marker to the specified sequence'. It also adds the useful qualifier that the sequence does not have to be active. It is clear enough to distinguish from delete_marker or update_marker, but it does not explicitly differentiate from the sibling add_marker_to_project_item.

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 description gives useful context — markers are for navigation or notes and can be added to an inactive sequence — so an agent knows it does not need to activate the sequence first. However, it does not state when to prefer this tool over alternatives like add_marker_to_project_item, update_marker, or delete_marker, nor does it list the common reasons for adding a marker.

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