add_ticket_comment

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

Annotations only declare readOnlyHint=false and openWorldHint=false; the description adds substantial context the annotations cannot: the entry is attributed to an API key rather than a person, the thread is capped at 500 entries, and a read_write key is mandatory while read keys are refused. These are real behavioral facts that affect invocation.

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?

Three short sentences, front-loaded with purpose, followed by attribution and constraint details. No filler, and each sentence carries information an agent needs before calling the tool.

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 mutation tool with no output schema, the description covers auth requirements, capacity limits, and attribution semantics, which is nearly everything needed. It does not address failure behavior beyond the read-key refusal (e.g., what happens at the 500-entry cap), leaving a small gap.

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 each parameter (projectId, ticketId, body) is documented in the schema, including that body is Markdown. The description restates the Markdown format but adds no syntax, format, or length guidance beyond what the schema already provides, so baseline 3 applies.

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?

States a specific verb and resource ('Add an entry to a ticket's thread') and immediately qualifies the artifact type (Markdown) and attribution. An agent can distinguish this from the sibling list_ticket_comments or create_ticket without opening any schema.

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 implies usage via the auth constraint ('Needs a read_write API key; a read key is refused and can only list and read'), which tells the agent not to attempt this with a read-only key. However, it never explicitly says when to add a comment versus updating or moving a ticket, so routing guidance is only inferred.

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