ACC.MCP

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

With no annotations provided, the description carries full burden. It discloses critical behavioral traits: it's a mutation tool (implied by 'Update'), requires specific permissions ('data:write' scope), and has field-level permission constraints (check permittedAttributes). It doesn't mention rate limits or destructive effects, but covers key operational context.

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?

Two concise sentences with zero waste. The first states the core purpose, the second adds essential permissions and constraint guidance. Every element 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 mutation tool with no annotations and no output schema, the description provides good context: purpose, partial update behavior, permissions, and field-level constraints. It could mention response format or error handling, but covers most critical aspects given the complexity.

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 fully documents all 16 parameters. The description adds minimal parameter semantics beyond the schema, only implying partial updates. Baseline 3 is appropriate when schema does the heavy lifting.

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 verb 'Update' and resource 'existing issue', specifying it's a partial update ('Only include the fields you want to change'). It distinguishes from sibling tools like aps_issues_create (create) and aps_issues_get (read).

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 provides explicit context for when to use it (update existing issues with partial fields) and mentions the prerequisite 'data:write' scope. It doesn't explicitly contrast with alternatives like aps_issues_create, but the context is clear.

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