create_library_metadata_by_ids_marker

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

Annotations already convey readOnly=false, destructive=false, and idempotentHint=true. The description adds a small behavioral cue by describing type as 'the type of marker to edit/create', suggesting the operation may create or update a marker, but it does not clarify overwrite behavior, permissions, or other side effects.

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 definition is compact and front-loaded with the action, followed by the endpoint and parameter list. There is no filler, although the endpoint line duplicates information in the tool name and the args list overlaps with the schema.

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 that creates markers with time offsets and attributes, the description omits what a marker actually is, when creating is preferable to updating, and how time offsets should be expressed. The output schema exists, but input/selection context and parameter constraints remain underspecified.

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 description coverage is 0%, so the description must define the parameters, but its definitions are mostly tautological. 'start_time_offset' is only described as 'the start time of the marker' without units, offset basis, or allowed values; 'attributes' gives no structure; 'type' does not enumerate valid values.

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 opens with 'Create a marker' and gives the POST endpoint, clearly identifying the action (create) and resource (library metadata marker). It is distinct from siblings like update_library_metadata_by_ids_marker_by_marker and delete_library_metadata_by_ids_marker_by_marker through the verb, though it does not explicitly call out that distinction.

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 choose this tool over the update or delete marker siblings. It does not state prerequisites, whether markers must already exist, or when creating vs editing is appropriate. Usage must be inferred from the tool name alone.

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