cancel_sync

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

Annotations only declare the safety profile (idempotentHint, destructiveHint=false, non-read-only). The description goes well beyond: no rollback of already-committed SQLite records, possible incomplete counts, terminal status returned for finished jobs, status=error for unknown/foreground jobs, and no new cloud request.

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?

Purpose and scope are front-loaded in the first clause, and every sentence conveys a distinct fact (rollback behavior, error cases, alternatives). It is dense, but a couple of semicolon-chained clauses could be trimmed without losing meaning.

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?

There is no output schema, yet the description explains the return value (terminal job status, finished jobs returned unchanged) and the error case. Combined with the mutation caveats and alternatives, an agent has everything needed to call this correctly.

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% for the single sync_id parameter, so the schema already documents its meaning and the required/minLength constraints. The description's 'exact sync_id' adds only a mild emphasis on exactness, so the 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 with scope: 'Cancel a queued/running background MCP sync by its exact sync_id.' It is immediately distinguishable from siblings like get_sync_status (inspection) and sync_data (resumption), which the description itself names.

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?

Explicitly routes the agent: 'Use get_sync_status to inspect progress and sync_data with user consent to resume via a new job.' It also states when the tool is inapplicable (unknown IDs, foreground jobs) and what those cases return.

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