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

No annotations are provided, so the description carries the full burden. It discloses a critical behavioral trait: counters are monotonic and a lower value fails validation with nothing written. It also mentions the tenant_key/Authorization header precedence, which is useful behavioral context. It does not describe the return value or error format, but the core behavioral risks are covered.

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 compact and front-loaded: it states the action and resource in the first sentence, then adds the critical monotonic constraint, then points to read-back tools. Every sentence earns its place with no redundancy.

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 5 parameters, no output schema, and no annotations, the description covers the essential behavioral constraints (monotonic counters, validation failure, tenant_key precedence) and points to sibling tools for reading back. It could mention what the response looks like or whether partial updates are atomic, but the description is largely complete for correct invocation.

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 100%, so the schema already documents all five parameters. The description adds meaning by explaining the monotonic semantics of counters and the merge behavior, which goes beyond the schema's per-key descriptions. However, it does not elaborate on pct/msg semantics beyond what the schema states, so the added value is moderate.

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 specific verb ('Report (or merge in)') and resource ('counters and/or pct/msg on a run, by id'), and distinguishes itself from sibling read tools by explicitly pointing to host.runs.get/wait/list for reading back. It is clear what the tool does and how it differs from related 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?

The description gives clear context for when to use the tool (reporting progress on a run) and mentions the monotonic counter constraint that affects usage. It does not explicitly state when not to use it or name alternatives beyond the read-back reference, but the context is sufficient for an agent to select it appropriately.

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