Find custom Slack emoji by case-insensitive name substring, returning image URLs or alias targets. Use it to locate emoji before referencing or managing them in a workspace.
List custom emoji by case-insensitive name substring, with URLs or alias targets. Needs emoji:read.
| Name | Required | Description | Default |
|---|---|---|---|
| query | No | ||
| workspace | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.2.3Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint and openWorldHint, so the description isn't burdened with the safety profile. It still adds real value by disclosing the required OAuth scope ('Needs emoji:read') and what the results contain (URLs or alias targets) — both facts absent from the structured fields.
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 compact sentences with no filler; the core capability and matching rule come first, the permission caveat second. Every clause 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?
Output schema exists so return-value explanation isn't required, and the auth requirement plus match semantics cover the essentials for a simple read tool. The only real gap is the unexplained 'workspace' parameter.
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 carry parameter meaning. It does explain 'query' well (case-insensitive name substring, implicitly optional since default is empty), but says nothing about the required 'workspace' parameter, leaving that half of the schema undocumented.
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 ('List custom emoji') plus the matching semantics ('case-insensitive name substring') and return shape ('URLs or alias targets'). It doesn't need sibling differentiation since none of the 29 siblings touch emoji, but it also names no alternative.
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?
Usage is implied by the substring-matching note and the permission requirement, so an agent can infer this is for looking up custom emoji by partial name. However, there is no explicit when-to-use, when-not-to-use, or pointer to any alternative tool.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.