Skip to main content
Glama
dmang-dev

mcp-ppsspp

by dmang-dev
OverviewSchemaRelated ServersScoreDiscussions
TypeScript
Hybrid

ppsspp_resume

Resume PSP emulation from a paused or stepping state. Use after an inspection sequence to continue execution. Idempotent: no effect if already running.

Instructions

PURPOSE: Resume PSP emulation from a paused/stepping state. USAGE: Counterpart to ppsspp_pause. Use after a paused inspection sequence. To step a single frame instead, use ppsspp_step. BEHAVIOR: Modifies emulator run state. Idempotent — resuming already-running is a no-op. RETURNS: Single line 'Emulation resumed'.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault

No arguments

Implementation Reference

  • src/tools.ts:499-503 (handler)
    The handler logic for ppsspp_resume tool: fires 'cpu.resume' via WebSocket and waits for emulation stepping state to become false, then returns 'Emulation resumed'.
    case "ppsspp_resume": {
  await pp.fireAndForget("cpu.resume");
  await pp.waitForState((s) => s.stepping === false);
  return ok("Emulation resumed");
}
  • src/tools.ts:290-297 (schema)
    The schema/definition for ppsspp_resume tool, including name, description, and inputSchema (empty object since no parameters needed).
    {
  name: "ppsspp_resume",
  description:
    "PURPOSE: Resume PSP emulation from a paused/stepping state. " +
    "USAGE: Counterpart to ppsspp_pause. Use after a paused inspection sequence. To step a single frame instead, use ppsspp_step. " +
    "BEHAVIOR: Modifies emulator run state. Idempotent — resuming already-running is a no-op. " +
    "RETURNS: Single line 'Emulation resumed'.",
  inputSchema: { type: "object", properties: {} },
  • src/tools.ts:405-613 (registration)
    The registration function that sets up both ListToolsRequestSchema (exposing TOOLS array) and CallToolRequestSchema (dispatching to the handler via switch/case). Handles the 'ppsspp_resume' case at line 499.
    export function registerTools(server: Server, pp: PpssppClient): void {
  server.setRequestHandler(ListToolsRequestSchema, async () => ({ tools: TOOLS }));

  server.setRequestHandler(CallToolRequestSchema, async (req) => {
    const { name, arguments: args = {} } = req.params;
    const p = args as Record<string, unknown>;
    const a = () => p.address as number;

    switch (name) {
      case "ppsspp_ping": {
        const r = await pp.call<{ version?: string; name?: string }>("version");
        return ok(`pong (${r.name ?? "PPSSPP"} ${r.version ?? "(unknown version)"})`);
      }

      case "ppsspp_get_info": {
        const status = await pp.call<{ game?: { id?: string; title?: string; version?: string } | null; paused?: boolean; stepping?: boolean }>("game.status");
        const lines: string[] = [];
        if (status.game) {
          lines.push(`Title:   ${status.game.title ?? "(unavailable)"}`);
          lines.push(`Disc ID: ${status.game.id ?? "(unavailable)"}`);
          lines.push(`Version: ${status.game.version ?? "(unavailable)"}`);
        } else {
          lines.push("No game loaded.");
        }
        const state = status.stepping ? "stepping (paused)" : status.paused ? "paused" : "running";
        lines.push(`State:   ${state}`);
        return ok(lines.join("\n"));
      }

      case "ppsspp_read8": {
        const r = await pp.call<{ value: number }>("memory.read_u8", { address: a() });
        return ok(`${addrHex(a())}: ${fmtHex(r.value)}`);
      }
      case "ppsspp_read16": {
        const r = await pp.call<{ value: number }>("memory.read_u16", { address: a() });
        return ok(`${addrHex(a())}: ${fmtHex(r.value)}`);
      }
      case "ppsspp_read32": {
        const r = await pp.call<{ value: number }>("memory.read_u32", { address: a() });
        return ok(`${addrHex(a())}: ${fmtHex(r.value)}`);
      }
      case "ppsspp_read_range": {
        const r = await pp.call<{ base64: string }>("memory.read", { address: a(), size: p.size });
        const bytes = Buffer.from(r.base64 ?? "", "base64");
        const hex = Array.from(bytes).map((b) => b.toString(16).padStart(2, "0").toUpperCase()).join(" ");
        return ok(`${addrHex(a())} [${bytes.length} bytes]:\n${hex}`);
      }
      case "ppsspp_read_string": {
        const r = await pp.call<{ value: string }>("memory.readString", { address: a(), type: "utf-8" });
        return ok(`${addrHex(a())}: ${JSON.stringify(r.value ?? "")}`);
      }

      case "ppsspp_write8": {
        await pp.call("memory.write_u8", { address: a(), value: p.value });
        return ok(`Wrote ${fmtHex(p.value)} → ${addrHex(a())}`);
      }
      case "ppsspp_write16": {
        await pp.call("memory.write_u16", { address: a(), value: p.value });
        return ok(`Wrote ${fmtHex(p.value)} → ${addrHex(a())}`);
      }
      case "ppsspp_write32": {
        await pp.call("memory.write_u32", { address: a(), value: p.value });
        return ok(`Wrote ${fmtHex(p.value)} → ${addrHex(a())}`);
      }
      case "ppsspp_write_range": {
        const bytes = Buffer.from(p.bytes as number[]);
        const base64 = bytes.toString("base64");
        await pp.call("memory.write", { address: a(), base64 });
        return ok(`Wrote ${bytes.length} bytes → ${addrHex(a())}`);
      }

      case "ppsspp_press_buttons": {
        await pp.call("input.buttons.send", { buttons: p.buttons });
        const pressed = Object.entries(p.buttons as Record<string, boolean>)
          .filter(([, v]) => v).map(([k]) => k);
        return ok(`Set buttons: ${pressed.length ? pressed.join("+") : "(all released)"}`);
      }
      case "ppsspp_press_button": {
        await pp.call("input.buttons.press", { button: p.button, duration: p.duration ?? 1 });
        return ok(`Pressed ${p.button} for ${p.duration ?? 1} frames (auto-released)`);
      }
      case "ppsspp_send_analog": {
        await pp.call("input.analog.send", { stick: p.stick, x: p.x, y: p.y });
        return ok(`Set analog stick ${p.stick} to (${p.x}, ${p.y})`);
      }

      case "ppsspp_pause": {
        // cpu.stepping is fire-and-forget per PPSSPP source ("No immediate
        // response. Once CPU is stepping, a 'cpu.stepping' event will be
        // sent."). Send it, then poll cpu.status until stepping=true.
        await pp.fireAndForget("cpu.stepping");
        await pp.waitForState((s) => s.stepping === true);
        return ok("Emulation paused");
      }
      case "ppsspp_resume": {
        await pp.fireAndForget("cpu.resume");
        await pp.waitForState((s) => s.stepping === false);
        return ok("Emulation resumed");
      }
      case "ppsspp_step": {
        const r = await pp.call<{ pc?: number }>("cpu.stepInto");
        return ok(`Stepped one instruction. PC: ${r.pc !== undefined ? addrHex(r.pc) : "(unknown)"}`);
      }
      case "ppsspp_reset": {
        await pp.call("game.reset");
        return ok("Game reset");
      }
      case "ppsspp_screenshot": {
        // PPSSPP's gpu.buffer.* events all require CORE_STEPPING_CPU (or GPU
        // stepping) state — they fail with "Neither CPU or GPU is stepping"
        // otherwise. We transparently pause→capture→resume so callers can
        // screenshot any time without managing pause state. If the emulator
        // was already paused, we leave it paused.
        //
        // source='render' (default) uses gpu.buffer.renderColor → reads the
        // active GPU render target. Safer: GPU_GetCurrentFramebuffer hits a
        // different code path than the crash-prone GPU_GetOutputFramebuffer.
        //
        // source='output' uses gpu.buffer.screenshot → reads the final
        // composited output (what's on screen, post scaling/shaders). Can
        // CRASH PPSSPP on some games: upstream has an `_assert_(buf != nullptr)`
        // after GPU_GetOutputFramebuffer that fires when the function returns
        // true with a null buffer (observed on some homebrew). We can't catch
        // a process abort from outside, but v0.1.2's auto-reconnect means MCP
        // recovers when PPSSPP is relaunched.
        const source = (p.source as string | undefined) ?? "render";
        const event  = source === "output" ? "gpu.buffer.screenshot" : "gpu.buffer.renderColor";
        const statusBefore = await pp.call<{ stepping?: boolean; paused?: boolean }>("cpu.status");
        const wasStepping = !!statusBefore.stepping;
        if (!wasStepping) {
          await pp.fireAndForget("cpu.stepping");
          await pp.waitForState((s) => s.stepping === true);
        }
        try {
          // type: "base64" returns the raw base64 payload; the default "uri"
          // returns a "data:image/png;base64,..." prefix which we'd have to strip.
          const r = await pp.call<{ base64?: string; uri?: string }>(event, { type: "base64" });
          let b64 = r.base64;
          if (!b64 && r.uri) {
            // Belt-and-suspenders: if PPSSPP returned a URI anyway, strip the prefix.
            const m = /^data:image\/png;base64,(.*)$/.exec(r.uri);
            if (m) b64 = m[1];
          }
          if (!b64) {
            throw new Error(`PPSSPP did not return screenshot data from ${event} (no game loaded, or framebuffer not readable?)`);
          }
          return {
            content: [
              { type: "text" as const, text: `Screenshot captured (source: ${source}, event: ${event}).` },
              { type: "image" as const, data: b64, mimeType: "image/png" },
            ],
          };
        } finally {
          if (!wasStepping) {
            try {
              await pp.fireAndForget("cpu.resume");
              await pp.waitForState((s) => s.stepping === false, { timeoutMs: 2000 });
            } catch { /* best-effort */ }
          }
        }
      }

      case "ppsspp_get_registers": {
        // PPSSPP's cpu.getAllRegs returns categories with PARALLEL arrays:
        //   { categories: [{ name, registerNames: [...], uintValues: [...], floatValues: [...] }] }
        // Not an array of {name, value} objects as I first assumed.
        const r = await pp.call<{
          categories?: Array<{
            name: string;
            registerNames?: string[];
            uintValues?: number[];
            floatValues?: string[];
          }>;
        }>("cpu.getAllRegs");
        const lines: string[] = [];
        for (const cat of r.categories ?? []) {
          lines.push(`── ${cat.name} ──`);
          const names = cat.registerNames ?? [];
          const vals  = cat.uintValues ?? [];
          for (let i = 0; i < Math.max(names.length, vals.length); i++) {
            const nm = names[i] ?? `r${i}`;
            const v  = vals[i];
            lines.push(`  ${nm.padEnd(8)} = ${v !== undefined ? addrHex(v) : "(unavailable)"}`);
          }
        }
        return ok(lines.join("\n") || "(no registers returned)");
      }

      case "ppsspp_breakpoint_add": {
        await pp.call("cpu.breakpoint.add", { address: a() });
        return ok(`Breakpoint added at ${addrHex(a())}`);
      }
      case "ppsspp_breakpoint_remove": {
        await pp.call("cpu.breakpoint.remove", { address: a() });
        return ok(`Breakpoint removed at ${addrHex(a())}`);
      }
      case "ppsspp_breakpoint_list": {
        const r = await pp.call<{ breakpoints?: Array<{ address: number; enabled?: boolean; condition?: string }> }>("cpu.breakpoint.list");
        const bps = r.breakpoints ?? [];
        if (bps.length === 0) return ok("No breakpoints set.");
        const lines = bps.map((b) => `  ${addrHex(b.address)} ${b.enabled === false ? "(disabled)" : ""}${b.condition ? ` if ${b.condition}` : ""}`);
        return ok(`${bps.length} breakpoint${bps.length === 1 ? "" : "s"}:\n${lines.join("\n")}`);
      }

      default:
        throw new Error(`Unknown tool: ${name}`);
    }
  });
}

Tool Definition Quality

A4.7/5.0
Behavior4/5

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

Describes modifying emulator run state, idempotency (no-op if already running). No annotations provided, so description carries burden. Could mention if any side effects, but likely none needed.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Very concise, structured with labeled sections (PURPOSE, USAGE, BEHAVIOR, RETURNS). Every sentence adds value, no redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Fully covers tool's purpose, usage, behavior, and return value. No missing information given zero parameters and no output schema.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Zero parameters, schema coverage 100%. Description adds no parameter info but baseline 4 for zero params is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Description clearly states it resumes PSP emulation from a paused/stepping state, using a specific verb and resource. It distinguishes from siblings by mentioning ppsspp_pause and ppsspp_step as alternatives.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly identifies as counterpart to ppsspp_pause, advises use after paused inspection, and suggests ppsspp_step for frame stepping. Provides clear when-to-use and when-not-to-use guidance.

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

Install Server

Other Tools

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/dmang-dev/mcp-ppsspp'

If you have feedback or need assistance with the MCP directory API, please join our Discord server